Jump to content

Persistent Cold Air in Florida


gsytch
 Share

Recommended Posts

Well I am trying to figure out this warm-up forecast for here tonight, which is 38-39 depending on source, when it is already 39.2F at 8:30 PM!

8:00 AM tomorrow is a long way off, I can't imagine we will stay at 39F all night, but that is what they are saying!!! :lol:

No watches or warning from the NWS for any of Florida except for the panhandle west of Lake City.

35.8F here at 10:30PM ...still waiting for the warm-up!!! :lol:

There are some some clouds moving in from the south ,but have not reached us yet..maybe that will reverse the downward trend!

I guess the temporary warm up came through overnight as I was shocked to wake up to temps in the low 50's!?!?!?!? Winds were actually from the south.

This I assume will be shortlived while the next one slams us later today :blink:

Larry 

Palm Harbor, FL 10a / Ft Myers, FL 10b

Link to comment
Share on other sites

Ok....now I'm getting a bit worried. After this rain tonight, tommorow night and saturday night its supposed to get down to possibly 20 degrees!

What do I do? I have Christmas lights.....should I wrap lights around my Bizmarkia's? I have 6 in the ground. I've got 3 outdoor extension cords. Do I wrap the spear then put the lights on the outside? I have never wrapped lights to protect palms before.......should I or shouldn't I?

They all seem to have handled temps down to 25 for several nights and for many hours at a time......but that extra 5 degrees is what I'm worried about.

Here are the Bizzies in question......help me save them!

I used bamoo poles and blankets to make a box of sorts, my bizzie is about 7 foot tall overall.

p.s. use two seperate light sources for heat I only used one and the bulb burnt out in the middle of the night.

Stuff happens :(

Link to comment
Share on other sites

It rained just enough last night to get everything good and wet.........now temps are hovering near freezing 33-34 degrees at 8:00 am. Thanks for the advice everyone on the proper way to do the lights, sheets, tarps ect.. My dilema now is everything is wet the wind is blowing in 10 mph gusts, still cloudy. I don't know if it might possibly dry out today above freezing......allowing me to wrap this afternoon under dryer conditions or should I wrap wet palms with electrical lights and sheets. :(

I'm leaning towards hoping for a dry-out and then wrapping. Man....this sucks. At least these Bizzies were somewhat established and are colder hardy than many types of palms you guys and gals are growing to the south. This is a major test for many species. Queens all over town will be tested as well. We will see how many P. roebs pull through as well.

One sidenote, I have a little greenhouse that I have been warming with a space heater, it has not been allowed to freeze...however it has gotten down close to freezing inside. This is where I house Kris's Borassus seedlings......these little guys have been real troopers, with no signs of damage near freezing.

David Simms zone 9a on Highway 30a

200 steps from the Gulf in NW Florida

30 ft. elevation and sandy soil

Link to comment
Share on other sites

Looks like the front is blowing through 9:00 am in the Florida Panhandle. The wind has really picked up 15-20 mph gusts. The best thing is the temps have warmed to 33-35 degrees and the ground is drying out. Hopefully this wetness will be gone before the temps drop again. This is what you can expect in the next few hours to those east and south of me. Slight warm-up, wind, partial clouds.

David Simms zone 9a on Highway 30a

200 steps from the Gulf in NW Florida

30 ft. elevation and sandy soil

Link to comment
Share on other sites

Whoa....not liking these apples!

A high of 40F!?!??!?! Incredible!

post-200-1262961169_thumb.jpg

Larry 

Palm Harbor, FL 10a / Ft Myers, FL 10b

Link to comment
Share on other sites

Thank you! Yeah, I have lived in the DC area my whole life, and while I was a kid in 77 (im 38 now) I very vividly remember the winter of 77/78 when the whole Chesapeake froze over as far down as south of the Bay Bridge. That was just amazing to see. The Potomac is now pretty frozen over, just about shore to shore and almost down to the Woodrow Wilson bridge. ITs not flat ice either. Since its been windy it is very chopped up jagged looking ice, sort of like ice jam looking i guess. Its been YEARS, probably 12 or more since we have seen the Potomac freeze like that. There IS ice forming on the Chesapeake too, but its not bad yet, but it is there and is noticeable. Have not seen ice on the bay in probably 20 years or more, save for maybe just a small lining just on the shoreline.

I was just in St. Pete in September for 10 days, so I did get to see it before this cold snap. It had been since 1991 since I had been to Tampa/ St. Pete, and MAN does it ever look alot different and BETTER! I was blown away by all the stuff that just grows down there. Our houseplants here turn into trees down there! THere were many times I was just stunned to be driving or walking along, and I see a big tree, then when I got close saw it was a giant scheffelera or rubber tree(ficus)..etc.

Is Kopick the place that is right down town on the water, just north of the Pier? The first place my friend took me right after he picked me up from TPA was a "Palmetum" that was right on the water in downtown St. Pete, not too far from the pier, and the Vinoy...etc. Ahhh... coffee / breakfast at the Vinoy.... good stuff! I had a great time down there, save for the day I laned ( it was pouring until we hit St. Pete) it was mostly sunny and pretty darn warm back then. There are ALOT of places down there that I want to visit, and many that I did visit that I want to go back to. My tow favorites were the Sunken Garden / Crescent lake ( that banyan is HUGE!) and of all places, Caddys on the beach / Sunset beach on Treasure Island.

As far as my friends yard, well, hes got TONS of stuff that we have as houseplants up here. Philodendrons, Dracenas (BIG ONES), some parlor palms, LOTS of Plumeria, scheffalera, rubber plants.... and the list goes on. He is in "interior" St. Pete, almost dead center of the peninsula, at what is the very southern most block of "Pinellas Park".

Anyway, I hope everything comes thru ok down there! St. Pete/ Tampa is very likely to be my future home, for multitudes of reasons. Its a fantastic climate, AND, they have pro ICE HOCKEY!!!! the best of both worlds! haha! Its not a matter of "if" anymore, its now just a matter of "when" for me. 38 winters here is enough, even though many in the last 10 years or so have been VERY MILD up here.

This might be a good time to consider moving here. Housing is much more reasonable - and yeah, the climate here is (usually) terrific. About the "houseplants" that grow outdoors - yep, we grow pothos right up into the trees - when they climb trees, those little leaves become giant. Philodendrons, dracaenas, ficus are all landscape plants for us. I have a shefflera tree by my house that is at least 15' maybe more, multi-trunked - it flowered this past summer. I think that D. lutescens is used as a popular "indoor" palm up north. Here, they're planted outdoors - and they grow like weeds.

It sounds as if your friend lives very close to us. We're just south of Pinellas Park, right on the border. And about Gizella Kopsick (I misspelt it this morning - frozen brain syndrome hehe) - it is right on the water near the pier.

Amazing to hear about the Chesapeake. Yeah, I remember the winter of '77-78 up there. It was most miserable. I was working in McLean at the time. Just cold-cold-cold and it kept snowing! ehhh. We left in March of '78 and as I got in my car to leave for FL, it started snowing again.

Yeah, its amazing to me not only what grows down there, but how BIG it gets! It all seems to just go wild! I hope most of it makes it through.

WHen I was down there in Sept. I was looking at the housing market, and rental market, and it blew my mind that I could have the same thing I have here (rent wise) for just about less than 1/2 the price, in a NICE neighborhood. I live in a very nice neighborhood here in NoVa, and I would like to find a neighborhood similar to this down there. We may rent first, while we are looking for a place.

Yep, its all freezing over. The last 3 days we had highs over 35, which was almost amazing, but thats gone for a while. We had the DC metro had 1and 1/2" of snow last night, and the high today, well we hit that at midnight last night while it was snowing. 31. Its 27.4 now, and falling. We wont see 32F again until probably tuesday. and the lows tonight, sat, and sun nights are going to be about 10-17F. YUK! The s now has stopped, the sun is out, but the winds are howling around 35MPH. It amazes me how much only 1.5 inches of snow blows around in this kind of wind. Its like a ground blizzard up here today. Its so thick at times in the first 10 feet or so off the ground that visibility is reduced to mere feet for brief periods when the big gusts come thru.

Link to comment
Share on other sites

Looks like the front is blowing through 9:00 am in the Florida Panhandle. The wind has really picked up 15-20 mph gusts. The best thing is the temps have warmed to 33-35 degrees and the ground is drying out. Hopefully this wetness will be gone before the temps drop again. This is what you can expect in the next few hours to those east and south of me. Slight warm-up, wind, partial clouds.

Can already see it coming, as my station plots are wacko........waiting for the big switcheroo in wind direction.......bet its going to hit like a hammer in a few more hours.

post-200-1262961359_thumb.png

Edited by spockvr6

Larry 

Palm Harbor, FL 10a / Ft Myers, FL 10b

Link to comment
Share on other sites

Here it comes..........wind direction and baro pressure charts dont lie.

post-200-1262965842_thumb.png

Edited by spockvr6

Larry 

Palm Harbor, FL 10a / Ft Myers, FL 10b

Link to comment
Share on other sites

forecast for tonight here in Titusville

w/underground - 31

weather.com ---- 36

NWS-------------- 37

No freeze watches or even warnings for east central Florida according to NWS,so what is one to make of the 31 forecast by w/underground? Plus the HIGH temp forecast for tomorrow is 43F!

Yesterday the NWS had my forecast at 31 for tonight? So is going to FREEZE tonight or NOT ? not that it really matters at this point?? :lol:

Scott

Titusville, FL

1/2 mile from the Indian River

USDA Zone COLD

Link to comment
Share on other sites

Local TV channels websites are forcasting lows of 24 tonight 25 tomorrow night and 28 to 30 on Sunday night :)

There is that 5 degrees I was hoping for......and it is drying out with the 10-15 mph wind. Satellite looks like we have clearing skies this p.m with more cloud cover coming in tonight. Somebody is smiling on me it seems :)

Hope I don't count my chickens before they hatch......but this might be good for you all to the east and south as well.

Up here in the Northwest Fl. panhandle, I feel a bit like the canary in the coal mine for all of you in the rest of the state......I'm still chirping and alive :)

David Simms zone 9a on Highway 30a

200 steps from the Gulf in NW Florida

30 ft. elevation and sandy soil

Link to comment
Share on other sites

Weather Channel is predicting highs in the mid upper 30's tomorrow for us and rain/snow/sleet with a low Sunday morning of 25* which I know will be much colder out here where I'm at. My Silver Saw Palmettos have damage from yesterday mornings 19.6* low. There are spots all over them... I'm not liking this at all!

BTW, it's sprinkling now with a temp of 58* at 1:40 pm.

Zone 9 Central Florida

Link to comment
Share on other sites

forecast for tonight here in Titusville

w/underground - 31

weather.com ---- 36

NWS-------------- 37

No freeze watches or even warnings for east central Florida according to NWS,so what is one to make of the 31 forecast by w/underground? Plus the HIGH temp forecast for tomorrow is 43F!

Yesterday the NWS had my forecast at 31 for tonight? So is going to FREEZE tonight or NOT ? not that it really matters at this point?? :lol:

Scott, that is curious. Forecasters are calling for freezes all the way to the coast for Sun/Mon in Cape Coral/Fort Myers. My lows those days are to be 31/31. I got to re-cover everything Sat. after the rain goes thru and it will all be ugly. I'm still formulating a plan to give my Areca concinna those few extra degrees that mean survival.

David, clouds have moved over Little Pine Island. It was supposed to rise to 70F (ha!) but the wind blowing over the 50+ degree Gulf is keeping temps in low 60s. I sure hope the clouds spare you, then make their way down here to shield us. Just a few extra degrees will make a huge difference. Tomorrow portends rain, high winds, temps in the 40s before the mercury plunges. No fun covering palms in those conditions.

Meg

Palms of Victory I shall wear

Cape Coral (It's Just Paradise)
Florida
Zone 10A on the Isabelle Canal
Elevation: 15 feet

I'd like to be under the sea in an octopus' garden in the shade.

Link to comment
Share on other sites

forecast for tonight here in Titusville

w/underground - 31

weather.com ---- 36

NWS-------------- 37

No freeze watches or even warnings for east central Florida according to NWS,so what is one to make of the 31 forecast by w/underground? Plus the HIGH temp forecast for tomorrow is 43F!

Yesterday the NWS had my forecast at 31 for tonight? So is going to FREEZE tonight or NOT ? not that it really matters at this point?? :lol:

Scott, that is curious. Forecasters are calling for freezes all the way to the coast for Sun/Mon in Cape Coral/Fort Myers. My lows those days are to be 31/31. I got to re-cover everything Sat. after the rain goes thru and it will all be ugly. I'm still formulating a plan to give my Areca concinna those few extra degrees that mean survival.

Meg we might have a misunderstanding ,that post is the forecast for tonight. W/underground has since revised their forecast for tonight to 36F, so they are all in aggreement on the forecast for no freeze here tonight. "After typing this I just rechecked the NWS service,and east central Florida is actually under a freeze WATCH tonight,even with forecast temps above freezing,which it wasn't when I posted the original post. The difference between a warning and a watch is... A warning they expect freezing temps...a watch freezing temps are possible"

My forecast as of right now for the next 2 nights after tonight, are for freezing temps... And for those nights freeze watch/warnings are posted.

w/underground -31, 29

weather.com---- 30, 30

NWS-------------- 28, 29

Edited by gsn

Scott

Titusville, FL

1/2 mile from the Indian River

USDA Zone COLD

Link to comment
Share on other sites

Nice to see 70's in south Florida today. One more arctic blast and the high pressure system will move east and allow for an easterly wind over Florida later next week. The end is in sight! ;)

Los Angeles/Pasadena

34° 10' N   118° 18' W

Elevation: 910'/278m

January Average Hi/Lo: 69F/50F

July Average Hi/Lo: 88F/66F

Average Rainfall: 19"/48cm

USDA 11/Sunset 23

http://cdec.water.ca.gov/cgi-progs/queryF?MTW

Link to comment
Share on other sites

We hope this is to end for the people in florida and other areas in east of united states ! The bad thing is today is only 8 january........

TEMP. JAN. 21/10 C (69/50 F), AUG. 29/20 C (84/68 F). DESERT BY OCEAN SUNNY DRY. RAIN: 220 MM (8.66 INCHS). BY OCEAN ZONE 11 NO FREEZES.

5845d02ceb988_3-copia.jpg.447ccc2a7cc4c6

Link to comment
Share on other sites

Larry,

Continue your graph. It's very interesting to see the sudden change in temp and wind direction.

Dick

Richard Douglas

Link to comment
Share on other sites

The temperature got up to 73 degrees today (one degree shy the January average daily high) here, only to have the next cold front start pushing through and dropping temperatures again.

In the past week I've had two nights with a low of 28.9F, and the rest ranging from 31 degrees to 38 degrees, with daily highs ranging from the low 50s to the low 60s.

My garden has taken a big freeze/frost hit already, more than it would have taken during a normal 9B winter (my USDA zone). Now my local weather forecaster is calling fof 28 degrees high ground to 22 degrees low ground for Sunday and Monday mornings. That forecast, if it should come to pass, will finish off my garden.

Mad about palms

Link to comment
Share on other sites

The temperature got up to 73 degrees today (one degree shy the January average daily high) here, only to have the next cold front start pushing through and dropping temperatures again.

In the past week I've had two nights with a low of 28.9F, and the rest ranging from 31 degrees to 38 degrees, with daily highs ranging from the low 50s to the low 60s.

My garden has taken a big freeze/frost hit already, more than it would have taken during a normal 9B winter (my USDA zone). Now my local weather forecaster is calling fof 28 degrees high ground to 22 degrees low ground for Sunday and Monday mornings. That forecast, if it should come to pass, will finish off my garden.

My hopes are that doesn't happen Walt. I hope the weather folks are being way too cold on this situation. It sure seems like they are most of the time.

Coastal San Diego, California

Z10b

Dry summer subtropical/Mediterranean

warm summer/mild winter

Link to comment
Share on other sites

HIGH of 38 degrees today!

forcast per NOAA for the next few days:

tonight low 22

Sat - 42/18

Sun - 45/16

Mon - 56/21

my low tonight is supposed to be about 18, to wet and to cold all at once. It can only get better.

Link to comment
Share on other sites

The temperature got up to 73 degrees today (one degree shy the January average daily high) here, only to have the next cold front start pushing through and dropping temperatures again.

In the past week I've had two nights with a low of 28.9F, and the rest ranging from 31 degrees to 38 degrees, with daily highs ranging from the low 50s to the low 60s.

My garden has taken a big freeze/frost hit already, more than it would have taken during a normal 9B winter (my USDA zone). Now my local weather forecaster is calling fof 28 degrees high ground to 22 degrees low ground for Sunday and Monday mornings. That forecast, if it should come to pass, will finish off my garden.

I think we hit 58* at one point. It's 52* right now at 6 pm with drizzle.

Zone 9 Central Florida

Link to comment
Share on other sites

The temperature got up to 73 degrees today (one degree shy the January average daily high) here, only to have the next cold front start pushing through and dropping temperatures again.

In the past week I've had two nights with a low of 28.9F, and the rest ranging from 31 degrees to 38 degrees, with daily highs ranging from the low 50s to the low 60s.

My garden has taken a big freeze/frost hit already, more than it would have taken during a normal 9B winter (my USDA zone). Now my local weather forecaster is calling fof 28 degrees high ground to 22 degrees low ground for Sunday and Monday mornings. That forecast, if it should come to pass, will finish off my garden.

I think we hit 58* at one point. It's 52* right now at 6 pm with drizzle.

Iw with ya Jay......high of 58F today. The temp was actually rising fairly rapidly earlier toay, along with a nice rise in humidity.....and then the front came through. The winds shifted from SE to NW and it rained. Then, the air started drying out and the temp dropping.......classic cold front!

But, if the winds stay NW, youll never hear me complain as this makes it much much harder to freeze (as the air has to come off the Gulf).

Heres another chart to please Dick :mrlooney:

post-200-1262993362_thumb.png

Edited by spockvr6

Larry 

Palm Harbor, FL 10a / Ft Myers, FL 10b

Link to comment
Share on other sites

Iw with ya Jay......high of 58F today. The temp was actually rising fairly rapidly earlier toay, along with a nice rise in humidity.....and then the front came through. The winds shifted from SE to NW and it rained. Then, the air started drying out and the temp dropping.......classic cold front!
Temp doesn't seem to be dropping too fast here. It's 50* right now at 6:57 pm. I believe it was 33* when I went to bed last night at around 10:00 pm ... then, this morning, it was in the low 40's when I looked at around 7:30 am. Strange indeed. I've just recently started becoming interested in weather temps and so forth... I have a lot to learn! I'm really curious to see if we actually get any snow from this cold... I'd actually like to see a few flurries if we're going to be cold anyway!

Zone 9 Central Florida

Link to comment
Share on other sites

I just saw NOAA numbers for Saturday Night: Palm Beach 30, Lauderdale, Miami & Homestead 32, Fairchild 35. Ouch!!!

Michael Norell

Rancho Mirage, California | 33°44' N 116°25' W | 293 ft | z10a | avg Jan 44/70F | Jul 80/108F avg | Weather Station KCARANCH310

previously Big Pine Key, Florida | 24°40' N 81°21' W | 4.5 ft. | z12a | Calcareous substrate | avg annual min. approx 52F | avg Jan 65/75F | Jul 83/90 | extreme min approx 41F

previously Natchez, Mississippi | 31°33' N 91°24' W | 220 ft.| z9a | Downtown/river-adjacent | Loess substrate | avg annual min. 23F | Jan 43/61F | Jul 73/93F | extreme min 2.5F (1899)

Link to comment
Share on other sites

On TV today I saw tourist sunning on Miami Beach. At 73 F that's still cool. They had to be Canadians.

Dick

Richard Douglas

Link to comment
Share on other sites

Now if you see them sunning tomorrow, on Miami Beach in the SNOW, they are definately Canadians!!! :lol:

Scott

Titusville, FL

1/2 mile from the Indian River

USDA Zone COLD

Link to comment
Share on other sites

33 degrees at 7:00......looks to be a long freeze of 10 plus hours tonight. We have clouds and wind. Is not shaping up to be a frost event, I'm thinking my temps will stay above 25 tonight.........at least that is my hope :unsure:

The timing of temps, rain, sun and wind......have been in my favor as far as last night, today and tonight.....feel bad for you further down the state who are ending your rain and getting cold tonight.....there may be some frozen rain on some palms in the state tonight.....my sympathies.

David Simms zone 9a on Highway 30a

200 steps from the Gulf in NW Florida

30 ft. elevation and sandy soil

Link to comment
Share on other sites

The timing of temps, rain, sun and wind......have been in my favor as far as last night, today and tonight.....feel bad for you further down the state who are ending your rain and getting cold tonight.....there may be some frozen rain on some palms in the state tonight.....my sympathies.

I voluntarily soaked my yard today.....ran the sprinklers for quite a few hours. I figured the palms would like to be well hydrated before getting frozen :blink:

Larry 

Palm Harbor, FL 10a / Ft Myers, FL 10b

Link to comment
Share on other sites

The timing of temps, rain, sun and wind......have been in my favor as far as last night, today and tonight.....feel bad for you further down the state who are ending your rain and getting cold tonight.....there may be some frozen rain on some palms in the state tonight.....my sympathies.

There has been very little rain except for up in the panhandle, where you are. I'm looking at radar for the entire state,and am wondering where the moisture is going to come from for us to get rain/snow. I know things can change with the weather on a dime, but there is virtually nothing on the radar right now indicating precipitation?

I also voluntarily soaked my yard today early, so it would dry out before sunset. I'm NOT convinced of this DROUGHT MODE = more cold tolerance?

Edited by gsn

Scott

Titusville, FL

1/2 mile from the Indian River

USDA Zone COLD

Link to comment
Share on other sites

I just saw NOAA numbers for Saturday Night: Palm Beach 30, Lauderdale, Miami & Homestead 32, Fairchild 35. Ouch!!!

Seriously? Palm Beach - 1F lower than us?? Cuz our NOAA temp on Saturday night (Lealman) is forecast to be (yech) 31F - same for Sunday.

What's amazing is Fairchild's predicted low. They're right near the water - and only forecast to be 4F warmer than us? Hard to understand. At least they'll warm up quick though. we won't. grrr.

On TV today I saw tourist sunning on Miami Beach. At 73 F that's still cool. They had to be Canadians.

or polar bears :lol:

I'm envious - it only got up to 54 today where I work, still with no heat, still with doors open, still very cold.

St. Pete

Zone - a wacked-out place between 9b & 10

Elevation = 44' - not that it does any good

Link to comment
Share on other sites

I believe this cold spell is going into the infamous freeze hall of fame: The Freeze of 2010!

Granted, the minimum is not as bad as '89 or '62, but as far as freeze damage is concerned, it will be bad. Not to mention the very possible sleet/snow flurries in central Florida.

Brevard County, Fl

Link to comment
Share on other sites

I believe this cold spell is going into the infamous freeze hall of fame: The Freeze of 2010!

Granted, the minimum is not as bad as '89 or '62, but as far as freeze damage is concerned, it will be bad. Not to mention the very possible sleet/snow flurries in central Florida.

Quite true! A "freeze" to call the worst in some respects. We've rooting for Florida [sadly Texas is already a loss :o

Los Angeles/Pasadena

34° 10' N   118° 18' W

Elevation: 910'/278m

January Average Hi/Lo: 69F/50F

July Average Hi/Lo: 88F/66F

Average Rainfall: 19"/48cm

USDA 11/Sunset 23

http://cdec.water.ca.gov/cgi-progs/queryF?MTW

Link to comment
Share on other sites

This weather is insane, snow in the forecast for Tampa Bay. Are you kidding? Its time to move further south.

NW Hillsborough County, FL (Near Tampa)

10 miles east of the Gulf of Mexico

Border of Zone 9b/10a

Lakefront Microclimate

Link to comment
Share on other sites

10 pm........30-32 degrees.........not a big cool down so far......still very cloudy with decreasing winds.

I have a question.......is the dew point (in freezing temperatures) the point at which you get frost?

If so our dew point is around 14 degrees...so there shouldn't be any frost tonight. What is the point of covering plants if not to protect from frost?

David Simms zone 9a on Highway 30a

200 steps from the Gulf in NW Florida

30 ft. elevation and sandy soil

Link to comment
Share on other sites

10 pm........30-32 degrees.........not a big cool down so far......still very cloudy with decreasing winds.

I have a question.......is the dew point (in freezing temperatures) the point at which you get frost?

If so our dew point is around 14 degrees...so there shouldn't be any frost tonight. What is the point of covering plants if not to protect from frost?

Pretty sure that is not really the case. I have seen frost plenty of times when the dewpoint was very very low, far below the actual air temp. That said, the lower the dewpoint, the less frost you will probably have. IF its 30, and the dewpoint is 27 or so, that could give you more frost , than if the dewpoint was say, 12, at that same temperature. At least that has been my experience anyway. Best of luck!

Link to comment
Share on other sites

10 pm........30-32 degrees.........not a big cool down so far......still very cloudy with decreasing winds.

I have a question.......is the dew point (in freezing temperatures) the point at which you get frost?

If so our dew point is around 14 degrees...so there shouldn't be any frost tonight. What is the point of covering plants if not to protect from frost?

I believe that you are correct on the dew point. However, the lower the dew point, the easier it is for the temp to plummet. Less moisture in the air, etc....

Coastal San Diego, California

Z10b

Dry summer subtropical/Mediterranean

warm summer/mild winter

Link to comment
Share on other sites

10 pm........30-32 degrees.........not a big cool down so far......still very cloudy with decreasing winds.

I have a question.......is the dew point (in freezing temperatures) the point at which you get frost?

If so our dew point is around 14 degrees...so there shouldn't be any frost tonight. What is the point of covering plants if not to protect from frost?

I believe that you are correct on the dew point. However, the lower the dew point, the easier it is for the temp to plummet. Less moisture in the air, etc....

That's been my experience as well. Westerly onshore winds can really kick up the humidity & help keep the temps up. The lack of wind w/ very low dew points and the temp can plummet. Even if there isn't any frost sub-freezing temps will do their damage.

Los Angeles/Pasadena

34° 10' N   118° 18' W

Elevation: 910'/278m

January Average Hi/Lo: 69F/50F

July Average Hi/Lo: 88F/66F

Average Rainfall: 19"/48cm

USDA 11/Sunset 23

http://cdec.water.ca.gov/cgi-progs/queryF?MTW

Link to comment
Share on other sites

10 pm........30-32 degrees.........not a big cool down so far......still very cloudy with decreasing winds.

I have a question.......is the dew point (in freezing temperatures) the point at which you get frost?

If so our dew point is around 14 degrees...so there shouldn't be any frost tonight. What is the point of covering plants if not to protect from frost?

The dew point is the temperature at which the moisture in the air will change state from a gas to a liquid (dew) or from a gas to a solid (frost). Frost or dew will not form until the air has cooled to the dew point. Now, when a thermometer says it's 30 that means the air right around the thermometer is 30 degrees. The air a few feet from that thermometer may not necessarily be 30. For instance, most people in the humid south have seen nights where the air temp, which is taken about 5 feet above ground level in open air, may be 36-38 with a dew point of 28 and yet rooftops and cars are covered in frost. The surfaces of rooftops and cars radiate their heat much faster than surrounding surfaces and the temperature of the air right around the rooftop and car has dropped to 28, and thus the moisture in the air has become a solid, frost. When frost has formed you can be sure that the air in the immediate area of the frost has reached it's dew point and is <= 32F.

Link to comment
Share on other sites

That's been my experience as well. Westerly onshore winds can really kick up the humidity & help keep the temps up. The lack of wind w/ very low dew points and the temp can plummet. Even if there isn't any frost sub-freezing temps will do their damage.

Humid air is slower to cool and slower to warm compared to drier air, so very dry air will allow the temps to drop quickly at night but will rise faster in morning when the sun comes out. This is why very dry desert areas can have such temperature extremes from night to day.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...