How far south in Mexico is cold damage ocurring?

[chinandega81]

I see areas within about 100 miles of the Rio Grande Valley  and south of the border with similar temps struggling to hit 30 around noon today. I am guessing tropicals and coconuts and royals will be decimated between just inland from La Pesca all the way to the US-Mexico border.

Even reliably warmer places further south, like Aldama and Soto la Marina, are near 40 at midday. Fortunately, it seems like areas this far south did not get below freezing temps or frozen precipitation up until now (and aren't forecasted to). Even Veracruz, at the southwest corner of the Gulf of Mexico will only have chilly highs in the 60s! That is the deep tropics, similar lattitude to Jamaica, Haiti, Belize etc.

This Siberian Express certainly did not stop at the border....even temperature gauges of the Texas coast well into the gulf have temps in the 20s and 30s in the middle of the day. Water temps near 70 well ofshore Padre Island with air temps in the 30s....pretty remarkable....in a sad way.

[Jimbean]

I'm amazed from a weather nerd and climate enthusiast myself over the Texas situation.  It is 3:15 PM local time in South Padre Island and it is still 29F.

 

I took a couple of screen shots earlier this morning for areas of northern Mexico.  Monterey was reading 21F and it appears to have had freezing temperatures about 30 miles short of Tampico.

[chinandega81]

The South Padre temps are crazy- i'm sure Laguna Madre had ice on spots neat the shore.  

 

This air mass is pretty insane. It looks like there will be a quicker turn around in Mexico vs. Texas regarding temps though.

[Jimbean]

It looks like a hard freeze about halfway down Tampaulipas state in Mexico.  We're talking about the elimination of zone 10 plants for probably another 50 miles going into Mexico. 

[palmsOrl]

21 hours ago, chinandega81 said:

I see areas within about 100 miles of the Rio Grande Valley  and south of the border with similar temps struggling to hit 30 around noon today. I am guessing tropicals and coconuts and royals will be decimated between just inland from La Pesca all the way to the US-Mexico border.

Even reliably warmer places further south, like Aldama and Soto la Marina, are near 40 at midday. Fortunately, it seems like areas this far south did not get below freezing temps or frozen precipitation up until now (and aren't forecasted to). Even Veracruz, at the southwest corner of the Gulf of Mexico will only have chilly highs in the 60s! That is the deep tropics, similar lattitude to Jamaica, Haiti, Belize etc.

This Siberian Express certainly did not stop at the border....even temperature gauges of the Texas coast well into the gulf have temps in the 20s and 30s in the middle of the day. Water temps near 70 well ofshore Padre Island with air temps in the 30s....pretty remarkable....in a sad way.

I have read historical reports of hard frost and even snow flurries having occured in the Blue Mountains of Jamaica, since you bring up the island.  I think one such occurrence was 1989.

-Michael

[Sabal_Louisiana]

Veracruz, 19N Lat, I see, fell no lower than 15C. Colder than normal but nowhere near record breaking.

Looks like Tampico at just north of 22 North Latitude will go down with a minimum of 4.4C with this one. That's right about 40F. All time record low for February there is about 3C.

Soto la Marina, Tamaulipas, just south of 24 north,  was down to 1.6C. 

Ciudad Victoria, to the east of there, hit -1C. But its at about 1000 ft above m.sl.

Monterrey, in the foothills of Nuevo Leon, reached 22F. That's exceptional even at their altitude.

San Fernando, just below 25N latitude  appears to be the southernomst lowland city in NE Mexico that fell below freezing. -1C this morning at that location.

[AnTonY]

If you want to see what's been hurting Texas and Mexico through these winters, have a look at the 500mb forecasts from any model of your choice (let's say, GFS). It's literally an ONSLAUGHT of big upper-level lows from the Pacific ALWAYS finding themselves in the Arizona-Baja-Northern Mexico region. It just never quits.

Even when there is no super-cold airmass like this current event, it still sucks because it can create day-after-day of dreary conditions, whether soggy with rain or just dank overcast. Just look at the sunshine hours of Brownsville and Tampico to see what I mean.

 

Edited February 17, 2021 by AnTonY

[Xenon]

3 hours ago, Sabal_Louisiana said:

Veracruz, 19N Lat, I see, fell no lower than 15C. Colder than normal but nowhere near record breaking.

Looks like Tampico at just north of 22 North Latitude will go down with a minimum of 4.4C with this one. That's right about 40F. All time record low for February there is about 3C.

Soto la Marina, Tamaulipas, just south of 24 north,  was down to 1.6C. 

Ciudad Victoria, to the east of there, hit -1C. But its at about 1000 ft above m.sl.

Monterrey, in the foothills of Nuevo Leon, reached 22F. That's exceptional even at their altitude.

San Fernando, just below 25N latitude  appears to be the southernomst lowland city in NE Mexico that fell below freezing. -1C this morning at that location.

Veracruz, especially by the time you get closer to Veracruz City (Heroica Veracruz) has never seen and probably never will see real cold. It's not just the low latitude but the Mexican coastline curves significantly to the southeast south of Tampico meaning there is a ton of very warm Gulf water between Veracruz and any cold front. It is safely lipstick palm territory and about as warm the Yucatan with record lows around 50F. 

[NorCalKing]

2 hours ago, AnTonY said:

If you want to see what's been hurting Texas and Mexico through these winters, have a look at the 500mb forecasts from any model of your choice (let's say, GFS). It's literally an ONSLAUGHT of big upper-level lows from the Pacific ALWAYS finding themselves in the Arizona-Baja-Northern Mexico region. It just never quits.

Even when there is no super-cold airmass like this current event, it still sucks because it can create day-after-day of dreary conditions, whether soggy with rain or just dank overcast. Just look at the sunshine hours of Brownsville and Tampico to see what I mean.

 

Which is our pain out west, of another winter turning into drought territory.

[Silas_Sancona]

2 hours ago, AnTonY said:

If you want to see what's been hurting Texas and Mexico through these winters, have a look at the 500mb forecasts from any model of your choice (let's say, GFS). It's literally an ONSLAUGHT of big upper-level lows from the Pacific ALWAYS finding themselves in the Arizona-Baja-Northern Mexico region. It just never quits.

Even when there is no super-cold airmass like this current event, it still sucks because it can create day-after-day of dreary conditions, whether soggy with rain or just dank overcast. Just look at the sunshine hours of Brownsville and Tampico to see what I mean.

 

Ya know.. ( since i live here ) This just hasn't been the case... at least this year.   Most lows that have come and gone have not  gone across AZ. ...or Baja / N. Mexico.  Most have passed across the northeastern part of the state and descend south as they cross New Mexico as they pass to the east.. ( Inside slider-type systems )  When  " big winter lows " do pass across AZ, ( either after coming ashore in S. Cal. / Northeast from N. Baja or Northern Mexico,  ..if not too far south ) we'll often get widespread rain/snow.. Haven't had that this year.  Decent rain/snow last winter here, but no huge freeze across Texas..  What could be missing?

Now the troughs,.. they've passed over the state.  Windy one is passing on by now.  As for any " Day after day dreary, rainy, overcast ..etc, etc " effects over Texas ( or other parts of the southeast ), after a trough passes us? 

...That is more of an effect of such troughs pulling moisture across Mexico -from the tropical East Pacific  -rather-  than ramming cold, North Pacific moisture down the lee side of the Rockies and throwing it over areas to the east.  In the absence of a major arctic air mass moving into the same area -at the same time- weather across effected parts of Texas /areas to their east might be showery/cloudy, but temperatures stay mild.. though not warm either.  ..a majority of the time anyway..

[AnTonY]

11 hours ago, NorCalKing said:

Which is our pain out west, of another winter turning into drought territory.

 

11 hours ago, Silas_Sancona said:

Ya know.. ( since i live here ) This just hasn't been the case... at least this year.   Most lows that have come and gone have not  gone across AZ. ...or Baja / N. Mexico.  Most have passed across the northeastern part of the state and descend south as they cross New Mexico as they pass to the east.. ( Inside slider-type systems )  When  " big winter lows " do pass across AZ, ( either after coming ashore in S. Cal. / Northeast from N. Baja or Northern Mexico,  ..if not too far south ) we'll often get widespread rain/snow.. Haven't had that this year.  Decent rain/snow last winter here, but no huge freeze across Texas..  What could be missing?

Now the troughs,.. they've passed over the state.  Windy one is passing on by now.  As for any " Day after day dreary, rainy, overcast ..etc, etc " effects over Texas ( or other parts of the southeast ), after a trough passes us? 

...That is more of an effect of such troughs pulling moisture across Mexico -from the tropical East Pacific  -rather-  than ramming cold, North Pacific moisture down the lee side of the Rockies and throwing it over areas to the east.  In the absence of a major arctic air mass moving into the same area -at the same time- weather across effected parts of Texas /areas to their east might be showery/cloudy, but temperatures stay mild.. though not warm either.  ..a majority of the time anyway..

I realize that the weather specifics are far more nuanced out West. After all, every little variance in pathway makes all the difference with regards to the weather effects that you end up seeing. However, I sort of generalized because I find that regardless of where exactly these upper-level systems set-up, the areas downstream from Texas into the rest of the South can still end up seeing the weather effects. (1) Often times, these upper-level lows out west have a poleward component that "outraces" everything, meaning that it sends down a cold front dammed along a N-S orientated mountain range into Texas and the South - this is what they refer to as cold-air damming (CAD). (2) Even if there is not strong poleward component, the upper-level low out west still creates divergent flow downstream (rear-right quadrant). As a result, you have lots of shortwaves that can emanate from the feature, and they can be strong enough to create the same effects as listed in (1.)

To be honest, it's actually a nice pattern in and of itself. The East Pacific moisture is in the high upper-levels, so the conditions aren't really gloomy, per-se - instead, it has what I like to call the "Pacific Cooler" effect, you have a nice, blue sky contrasting nicely with streams of sirius clouds. However, when the pattern is combined with the unimpeded Arctic airmasses east of the Rockies, then all hell breaks loose. When the weather gets cold enough, you end up with wave-after-wave of wintry weather like what Texas and parts of the South are seeing right now. (1) The upper level pattern creates a tropical moisture surge from the south that ends up  "overrunning" because the Arctic air is shallow - the result is gloomy overcast and/or heavy precip with low cloud bases. (2) The shallow Arctic air is so cold, it cools the overriding air to the dewpoint, "wringing" out precip - disturbances that bring little more than sirius clouds and breezes out West end up wreaking all sorts of wintry havoc in Texas and the South.

Having that said, I do agree that there are differences in weather patterns that result from the position of the upper lows. I'd say that the "inside-sliders" are the worst for Texas concerning the combination of cold air from the north (right down the Rockies spine), combined with overriding moisture - in contrast, a low farther west in California and/or the Baja can offer periods of nicer weather in Texas ... unless a strong enough shortwave emanating from it drops a cold front far enough south.

Edited February 17, 2021 by AnTonY

[NorCalKing]

Yeah, basically this pattern sucks for both of us. I'm already dreading fire season seeing how dry this "winter" has been for us out west. Hopefully things turn around for Texas sooner. Nobody deserves what you guys are seeing.

[AnTonY]

On 2/17/2021 at 5:01 PM, NorCalKing said:

Yeah, basically this pattern sucks for both of us. I'm already dreading fire season seeing how dry this "winter" has been for us out west. Hopefully things turn around for Texas sooner. Nobody deserves what you guys are seeing.

Yep. But, ever since I've actually been looking into upper-level patterns, satellite images, etc - it's always amazing to me how much of a difference temperature makes with regards to how the weather pattern plays out. The small shortwave that passes by with little fanfare over California can create major winter storm and huge overcast over Texas/Southern US whenever there is Arctic air in place.

[tacobender]

The Sierra Madre range must have stopped the cold front from going east. Normal weather in state of Sonora. Sorry for your losses.

[Silas_Sancona]

10 minutes ago, tacobender said:

The Sierra Madre range must have stopped the cold front from going east. Normal weather in state of Sonora. Sorry for your losses.

Sierra Madre/ Mex. Plateau definitely keep the cold away from the west side of Mexico, at least this year..  I see Alamos is supposed to be in the mid 80s- low 90s/ No lows below 54F for the next 10 days, ( CENTRO ISONORAA2 WX station there ) and has already hit the mid 90s earlier in the month.. And they're at roughly the same elevation as Chandler ( 1273 ft there, 1210ft = DTG station in Chandler ).. At the same time, Guaymas is only looking at mid 70s-mid 80s during the same period.  Crazy.

[AnTonY]

Hermosillo is the same latitude as Houston ...

I'm thinking the heat that they see in Hermosillo, Alamos, etc could be compressional warming via downsloping of the arctic airmasses that try to cross into the region.

[Silas_Sancona]

10 minutes ago, AnTonY said:

Hermosillo is the same latitude as Houston ...

I'm thinking the heat that they see in Hermosillo, Alamos, etc could be compressional warming via downsloping of the arctic airmasses that try to cross into the region.

Been warm all winter.. " Record " low for Alamos itself is 23F ( ..or 25F, from another source.. )  Record high is 121F, set in 1976.  Have noted numerous royals down there when looking over the area. Western Mexico in general is much warmer than areas at the same latitude on the eastern side of the continent. A big reason tropical plants/animals range further north there than on the east side.  Large creek located in the Reserve southeast of the city is the most diverse area in the entire Northern hemisphere for birds. Is also home to the northern most species of Leaf Frog outside the tropics.  Still finding new species/ northern extant ranges of tropical stuff there as well.

 Decades worth of research done by ASDM alum Mark Dimmitt and Thomas Van Devender ( among others ) are excellent reads on the region..

[tacobender]

Most weather in Guaymas, San Carlos area in winter comes from South, West or North. Somewhat rare for winds and weather from the east.

[AnTonY]

6 hours ago, Silas_Sancona said:

Been warm all winter.. " Record " low for Alamos itself is 23F ( ..or 25F, from another source.. )  Record high is 121F, set in 1976.  Have noted numerous royals down there when looking over the area. Western Mexico in general is much warmer than areas at the same latitude on the eastern side of the continent. A big reason tropical plants/animals range further north there than on the east side.  Large creek located in the Reserve southeast of the city is the most diverse area in the entire Northern hemisphere for birds. Is also home to the northern most species of Leaf Frog outside the tropics.  Still finding new species/ northern extant ranges of tropical stuff there as well.

 Decades worth of research done by ASDM alum Mark Dimmitt and Thomas Van Devender ( among others ) are excellent reads on the region..

 

1 hour ago, tacobender said:

Most weather in Guaymas, San Carlos area in winter comes from South, West or North. Somewhat rare for winds and weather from the east.

All true. I just imagined that with mountain ranges to the east, any weather from that direction would come in with significant compressional warming. Like how Los Angeles has those Santa Anna events, for instance.

[Silas_Sancona]

1 minute ago, AnTonY said:

 

All true. I just imagined that with mountain ranges to the east, any weather from that direction would come in with significant compressional warming. Like how Los Angeles has those Santa Anna events, for instance.

Too far south to be influenced by the same factors that contribute to the Santa Anas.. though i'm sure there can be similar events under the right circumstances at times when polar fronts actually reach the area.. ( uncommon most years ) At least in the winter.

Overall "flow" normally switches east/ south easterly once the center of the Monsoon high has built over Mexico/ Southwest U.S./ Southern Plains in June/July..  Same pattern ( winds blowing west off the Gulf of Mexico ) helps bring torrential rains to some of the detached ridges / Sierra Oriental in Summer. Is why tropical disturbances/ the occasional big hurricane that zips across the Gulf of Mex. or tracks west northwest thru Texas after landfall can reach AZ/ S. Cal. ( big slug of remnant moisture ) during our Monsoon season, if an ideal year.