Upcoming cold for the South (Models, Maps, Discussions)

[jasons2k]

For some reason, I'm no longer stressed. Whatever happens, happens. I can't do anything about it. Except pray for a miracle. I might be giving my right arm to Houston Garden Center though.

[Tyler]

0z GFS 90 hour:

Cold air spreading across SE TX:

[jasons2k]

My big fear is that we get rain on Saturday and that there are puddles/wet roads on Saturday night, and then we dip to well below 32 and it freezes. Could be a real mess Sunday morning. I also think we need to watch the back edge of this precip. If it lasts later into Saturday, then I would not be surprised to see it end in a wintry mix since we will be entering such a cold airmass. Just some thoughts...we will need to watch models closely over the next few days. Would not even be surprised to see some isolated flurries on Saturday evening.

Extreme, I agree, any standing water Saturday night could freeze and cause very tricky travel.

That is actually something I am not concerned about. The ground is very warm and anything on overpasses will evaporate before it gets to freezing.

[weatherrabbit_tx]

20 to 22 degrees at hooks airport sunday am

[Tyler]

GFS day 4: Better wear a heavy coat!:

[Tyler]

And the coldest timeframe, hour 102:
Lower to mid 20's across SE TX (under ideal radiational cooling of course, which we could have):

[Tyler]

Well folks, get ready, you think its cold tonight, well, your in for a big suprise (well, not anymore ) this weekend. Bundle up!

[Kludge]

0z GFS day 3.5:

Here it comes:

If this were to verify.....

D ... A ... M ... N !!! <brrrr>

[PTPatrick]

SO will this cold air be in place in time for hte surge of moisture to come from the gulf over Southern LA, MS and AL and give us Katrina Victims so snow? Any thoughts? Looks to be an issue of timing...if the cold air can get in later friday night/early saturday and the moisture holds off til saturday nigh we are in business...ETA looks slower with the moisture, whilst the GFS looks fast having most of the moisture east of mobile(and east of the cold air) by Saturday evening...

Mobile NWS is being very quiet on this..as is NOLA

[Tyler]

0z GFS day 3.5:

Here it comes:

If this were to verify.....

D ... A ... M ... N !!! <brrrr>

With all models now in agreement, it very well could!

[Tyler]

SO will this cold air be in place in time for hte surge of moisture to come from the gulf over Southern LA, MS and AL and give us Katrina Victims so snow? Any thoughts? Looks to be an issue of timing...if the cold air can get in later friday night/early saturday and the moisture holds off til saturday nigh we are in business...ETA looks slower with the moisture, whilst the GFS looks fast having most of the moisture east of mobile(and east of the cold air) by Saturday evening...

Mobile NWS is being very quiet on this..as is NOLA

If I were you, I'd watch this situation very closely. It looks like SE TX will have all available moisture gone by the time the coldest air rushes in. However, points eastward, as the moisture continues its slow push to the east, could experience some wintry precipitation. Obvously right now, its too soon to make any huge calls, just something to watch!

[Tyler]

GFS MOS temp guidance has gone WAY down with temps, but they are still too warm, as the GFS is having trouble with this arctic airmass (just like early December)

It wants a high of 57 Saturday. With clouds and rain in the morning, we will likely stay stuck in the 40's, especially with such strong cold air advection. Saturday night GFS MOS says 32. Much better than earlier's 41, but still a couple of degrees too warm. Lets go with 27 for now. Sunday's high is 58, again, thats too warm, lower 50's seem likely at this point.

http://www.srh.noaa.gov/data/Guidance/G ... KIAH.1.txt

[Tyler]

We may not be done with the cold air folks...

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _180.shtml

I'm ready for spring.

[Extremeweatherguy]

GFS MOS temp guidance has gone WAY down with temps, but they are still too warm, as the GFS is having trouble with this arctic airmass (just like early December)

It wants a high of 57 Saturday. With clouds and rain in the morning, we will likely stay stuck in the 40's, especially with such strong cold air advection. Saturday night GFS MOS says 32. Much better than earlier's 41, but still a couple of degrees too cool. Lets go with 27 for now. Sunday's high is 58, again, thats too warm, lower 50's seem likely at this point.

http://www.srh.noaa.gov/data/Guidance/G ... KIAH.1.txt

GFS MOS temp. guidance is always a good 5-15 degrees too high in these situations.

[Tyler]

GFS MOS temp guidance has gone WAY down with temps, but they are still too warm, as the GFS is having trouble with this arctic airmass (just like early December)

It wants a high of 57 Saturday. With clouds and rain in the morning, we will likely stay stuck in the 40's, especially with such strong cold air advection. Saturday night GFS MOS says 32. Much better than earlier's 41, but still a couple of degrees too cool. Lets go with 27 for now. Sunday's high is 58, again, thats too warm, lower 50's seem likely at this point.

http://www.srh.noaa.gov/data/Guidance/G ... KIAH.1.txt

GFS MOS temp. guidance is always a good 5-15 degrees too high in these situations.

Yes, I agree, but since 12z, it has come down by 10 degrees, and will likely continue this trend into 12z tommorow.

[LAwxrgal]

And the coldest timeframe, hour 102:
Lower to mid 20's across SE TX (under ideal radiational cooling of course, which we could have):

I'm cold just looking at that map! At 102 hours, I have the -10 over my area. Just what would that translate to if this were to verify? My local NWS (New Orleans) has been hush about this.

[Extremeweatherguy]

And the coldest timeframe, hour 102:
Lower to mid 20's across SE TX (under ideal radiational cooling of course, which we could have):

I'm cold just looking at that map! At 102 hours, I have the -10 over my area. Just what would that translate to if this were to verify? My local NWS (New Orleans) has been hush about this.

Actually, reserve is more in the -8C 850mb area (may be -9C)...but if you guys were to get perfect radiational cooling...this could translate to -6C or -7C (may be -8C) at ground level which would be 19-21 degrees! That is if you get PERFECT radiational cooling though. Either way...IF this verifies...most of the Northern Gulf will see lows below 27 and some places may sneak below 20. Stay tuned.

[beachbum_al]

I was right! Not that I am an expert or anything on weather. But I kept saying that the cold weather would be hear around Mardi Gras time and look! So does anyone know what the models are saying for the 25th of February?

It is cold here. Not too cold but cool. The low according to the NWS on my computer is 33 degrees out of Mobile. And I have to agree the weather people are not saying much about this weekend.

[Cookiely]

I THINK I WILL FINALLY GET TO WEAR MY COAT THIS SEASON ON MONDAY MORNING.
000
FXUS62 KTBW 080737
AFDTBW

WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
237 AM EST WED FEB 8 2006

.SHORT TERM(TODAY - FRIDAY)...AMPLIFIED PROGRESSIVE PATTERN CONTINUES.
MODELS THIS MORNING ARE AGAIN IN GOOD AGREEMENT SO WILL USE A BLEND.
COOLER DRIER AIR MASS IN THE WAKE OF A COLD FRONT NOW ACROSS THE SOUTHERN
PENINSULA THIS MORNING WILL ENSURE AMPLE SUNSHINE AND DRY COOL CONDITIONS
ACROSS THE FORECAST AREA TODAY. DESPITE THE SUNSHINE THOUGH WEAK COOL
AIR ADVECTION AND THE DRY AIR MASS WILL KEEP TEMPERATURES FROM RISING
MUCH WITH READINGS ONLY CLIMBING INTO THE LOWER 60S NORTH INTO CENTRAL
ZONES AND UPPER 60S FAR SOUTH.

TONIGHT WEAK HIGH PRESSURE FROM THE WESTERN GULF WITH THE RIDGE AXIS
EXTENDING EAST ACROSS THE PENINSULA WILL SUPPORT CLEAR SKIES AND LIGHT
WINDS. THESE CONDITIONS WILL SUPPORT GOOD RADIATIONAL COOLING...WHICH
WILL RESULT IN POCKETS OF FREEZING TEMPERATURES ACROSS THE NATURE COAST.
GRIDDED DATA SHOW ONLY 1 TO 2 HOURS DURATIONS OF TEMPS AOB FREEZING...SO
WILL HOLD OFF ON A FREEZE WATCH...BUT WILL MENTION NEAR FREEZING TEMPS
POSSIBLE IN THE NORMALLY COLDER LOCATIONS IN THE ZONES. ACROSS THE REST
OF THE FORECAST AREA TEMPERATURES WILL DROP INTO THE LOWER AND MIDDLE
40S.

ON THURSDAY FAST PROGRESSIVE FLOW PATTERN WILL SEND ANOTHER SHORT WAVE
TROUGH ACROSS THE SOUTHEASTERN STATES WITH ITS ATTENDANT REINFORCING
COLD FRONT (REINFORCING SURGE OF COOL DRY AIR) MOVING THROUGH THE FA
DURING THE DAY. LACK OF MOISTURE RETURN AHEAD OF THIS FRONT MEANS A
DRY FRONTAL PASSAGE WITH ONLY A PERIOD OF GUSTY WINDS AND BROKEN
STRATO-CU CLOUDS EXPECTED DURING THE AFTERNOON. THURSDAY NIGHT SURFACE
HIGH PRESSURE WILL BUILD IN FROM THE WEST...WITH THE HIGH SETTLING IN
OVER THE NORTHERN PENINSULA BY EARLY FRIDAY MORNING. THE COMBINATION
OF CLEAR SKIES...VERY DRY AIR MASS...AND A VERY LIGHT NORTHERLY DRAINAGE
FLOW WILL LEAD TO EXCELLENT RADIATIONAL COOLING WITH FREEZING TEMPERATURES
LIKELY OVER THE NATURE COAST...AND UPPER 30S TO LOWER 40S CENTRAL AND
SOUTH BY EARLY FRIDAY MORNING. CURRENT GUIDANCE AND GRIDDED DATA SHOWS
ABOUT 5-6 HOURS OF BELOW FREEZING TEMPERATURES OVER THE NATURE COAST...SO
HAVE POSTED A FREEZE WATCH FOR THESE AREAS. IN ADDITION THE CALM WINDS
AND HIGH GROUND MOISTURE WILL SUPPORT AREAS OF FROST OVER THE NATURE
COAST...WITH PATCHY FROST DOWN THROUGH CENTRAL AND SOUTHERN INTERIOR
LOCATIONS. AFTER A COLD START FRIDAY MORNING TEMPERATURES WILL REBOUND
INTO THE UPPER 60S TO AROUND 70 AS THE SURFACE HIGH SHIFTS SOUTH WITH
AN ONSHORE FLOW DEVELOPING DURING THE AFTERNOON UNDER MOSTLY SUNNY
SKIES. MAV/MET TEMPERATURE GUIDANCE AGAIN CLOSE WITH BELOW NORMAL
READINGS CONTINUING THROUGH THE PERIOD.

&&

.LONG TERM(FRI NIGHT - TUES)...TEMPERATURES WILL WARM UP A BIT ON
SATURDAY WITH SOUTHWESTERLY FLOW AT THE SURFACE AHEAD OF AN APPROACHING
COLD FRONT. THERE IS BETTER AGREEMENT BETWEEN MODELS AT THIS TIME
REGARDING THE ARRIVAL AND DEPARTURE OF THE BULK OF THE FRONT...WHICH
IS IN GOOD AGREEMENT WITH THE CURRENT TIMING...POPS AND QPFS IN
THE GRIDS. THEREFORE WILL KEEP CURRENT VALUES AND WAIT FOR FUTURE
MODEL RUNS TO MAKE ADDITIONAL ADJUSTMENTS. EXPECT PASSING SHOWERS
FROM SATURDAY EVENING THROUGH SUNDAY MORNING. THE FRONT SHOULD CLEAR
THE NORTHERN HALF OF THE CWA BY DAYBREAK ON SUNDAY...AND THE SOUTHERN
COUNTIES BY NOON.

FOR SUNDAY EVENING DGEX/GFS SHOW FAIR AGREEMENT IN DEVELOPING A
BROAD STRONG HIGH PRESSURE CENTER OVER THE SOUTHEAST US AND EXPANDING
INTO THE GULF AND FLORIDA BY MONDAY MORNING. WITH GENERALLY CLEAR
SKIES AND NORTHERLY FLOW AT THE SURFACE FROM THE EASTERN HALF OF
THE HIGH...ADVECTION OF CONTINENTAL DRY AND COLD AIR WILL COMBINE
WITH EFFICIENT RADIATIONAL COOLING CONDITIONS OVERNIGHT TO BRING
DOWN TEMPERATURES ON MONDAY MORNING. MOST OF THE NATURE COAST
COUNTIES WILL REACH FREEZING VALUES WITH LEVY AND CITRUS COUNTIES
DROPPING TO UPPER 20S RIGHT BEFORE SUNRISE....AND UPPER 30S
ELSEWHERE. THE HIGH EXPANDS WELL INTO THE ATLANTIC AND FLATTENS
OUT ON TUESDAY BRINGING EASTERLY WINDS WHICH WILL HELP IN WARMING
UP TEMPERATURES...AROUND 5 TO 7 DEGREES WARMER THAN THE PREVIOUS
DAY.

&&

[wxman22]

Here's the latest discussion from the NWS in Houston:AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
400 AM CST WED FEB 8 2006

.DISCUSSION...
SURFACE HIGH PRESSURE RIDGE CONTINUES ACROSS SE TX EARLY THIS
MORNING. SCATTERED HIGH CLOUDS ARE STREAMING OVERHEAD AND WILL
CONTINUE AT LEAST THROUGH THE MORNING...WITH SKIES BECOMING MOSTLY
CLEAR BY LATE AFTERNOON. TEMPS WILL BE 5 TO 10 DEGREES WARMER TODAY
WITH LIGHT SOUTHWEST SURFACE WINDS DEVELOPING. THE NEXT COLD FRONT
WILL SWEEP ACROSS THE CWA AFTER MIDNIGHT LOWERING MAX TEMPS THURSDAY.

SOUTHERN STREAM 500 MB LOW WILL APPROACH FROM THE WEST THURSDAY
NIGHT...AND SHEAR OUT OVER TEXAS DURING THE DAY FRIDAY. MOISTURE WILL
BEGIN TO INCREASE OVERNIGHT THURSDAY NIGHT IN ADVANCE OF THIS
SYSTEM...WITH 30 TO 40 KNOT LOW LEVEL JET DEVELOPING FRIDAY MORNING.
THIS WILL HELP PWS TO INCREASE TO 1.2-1.3 INCHES ACROSS THE SOUTHERN
HALF OF SE TX DURING THE DAY FRIDAY. MEANWHILE...STRONG COLD FRONT
WILL REACH SE TX DURING THE LATE AFTERNOON HOURS HELPING TO SERVE AS
A FOCUS FOR SHRA DEVELOPMENT. DECIDED TO BRING LOW POPS INTO THE
FORECAST BEGINNING LATE THURSDAY NIGHT...AND HAVE INCREASED POPS TO
HIGH CHANCE CATEGORY FOR FRIDAY. TEMPERATURE FORECAST WILL BE
COMPLICATED THESE PERIODS. LOWS THURSDAY NIGHT WILL LIKELY OCCUR
BEFORE CLOUD COVER MOVES IN WHILE HIGHS FRIDAY WILL BE LIMITED BY
CLOUDS/RAIN. ONGOING TEMPERATURE FORECAST LOOKS GOOD.

STRONG COLD ADVECTION DEVELOPS FRIDAY EVENING AS FRONT PUSHES WELL
SOUTH INTO THE GULF. WILL END RAIN CHANCES FROM NORTH TO SOUTH LATE
FRIDAY NIGHT WITH SKIES GOING PARTLY CLOUDY AREAWIDE BY MIDDAY
SATURDAY. LATEST GFS HAS FLIP-FLOPPED BACK TO A COLDER SOLUTION
SIMILAR TO THE ECMWF WHICH HAS BEEN MORE CONSISTENT RUN-TO-RUN. ECMWF
STILL SHOWS 850 MB TEMPS DROPPING SIGNIFICANTLY BY 00Z SUNDAY TO
AROUND -4C OVER HOUSTON AND -7C OVER OUR NRN ZONES. WILL STICK WITH
FREEZING TEMPS MOST INLAND AREAS SATURDAY NIGHT AND FOR THE NE ZONES
SUNDAY NIGHT. WITH LOTS OF SUNSHINE...TEMPS SHOULD WARM BACK UP TO
NEAR NORMAL BY MONDAY. LATEST MODEL RUNS HAVE BACKED OFF THE SHORTWAVE
THAT WAS PROGGED EARLY NEXT WEEK...SO REMOVED RAIN CHANCES TUESDAY.

35

&&