TX winter wx thread: Spring-like pattern

[TexasStooge]

Here you go folks...

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE FORT WORTH TX
256 PM CST WED JAN 23 2008

...WINTER STORM WATCH ISSUED FOR SLEET AND FREEZING RAIN THURSDAY
NIGHT INTO FRIDAY FOR WESTERN HALF OF NORTH TEXAS...

.SLEET IS EXPECTED TO INITIALLY DEVELOP LATE THURSDAY EVENING IN
FAR WESTERN ZONES OF NORTH TEXAS...THEN CHANGE TO FREEZING RAIN AS
PRECIPITATION SPREADS EAST THROUGH MORNING. WINTRY CONDITIONS CAN
BE EXPECTED ALONG AND WEST OF A LINE FROM
SHERMAN...MESQUITE...WACO...TO TEMPLE. TEMPERATURES WILL LIKELY
REMAIN BELOW FREEZING THROUGH THE MORNING HOURS AND ENOUGH ICE
ACCUMULATION TO IMPACT TRAVEL IS EXPECTED...ESPECIALLY IN FAR
WESTERN ZONES. CONDITIONS WILL IMPROVE FRIDAY AFTERNOON AS
TEMPERATURES WARM ABOVE FREEZING AND THE SYSTEM MOVES EAST.

TXZ091>093-100>104-115>120-129>134-141>145-156>159-240430-
/O.NEW.KFWD.WS.A.0001.080125T0600Z-080125T1800Z/
MONTAGUE-COOKE-GRAYSON-YOUNG-JACK-WISE-DENTON-COLLIN-STEPHENS-
PALO PINTO-PARKER-TARRANT-DALLAS-ROCKWALL-EASTLAND-ERATH-HOOD-
SOMERVELL-JOHNSON-ELLIS-COMANCHE-MILLS-HAMILTON-BOSQUE-HILL-
LAMPASAS-CORYELL-BELL-MCLENNAN-
INCLUDING THE CITIES OF...BOWIE...NOCONA...GAINESVILLE...
SHERMAN...DENISON...GRAHAM...OLNEY...JACKSBORO...DECATUR...
BRIDGEPORT...DENTON...LEWISVILLE...FLOWER MOUND...THE COLONY...
PLANO...BRECKENRIDGE...MINERAL WELLS...WEATHERFORD...BRIAR...
FORT WORTH...ARLINGTON...DALLAS...ROCKWALL...CISCO...EASTLAND...
RANGER...GORMAN...STEPHENVILLE...DUBLIN...GRANBURY...
OAK TRAIL SHORES...GLEN ROSE...CLEBURNE...BURLESON...WAXAHACHIE...
ENNIS...MIDLOTHIAN...GLENN HEIGHTS...COMANCHE...DE LEON...
GOLDTHWAITE...HAMILTON...HICO...CLIFTON...MERIDIAN...
VALLEY MILLS...HILLSBORO...LAMPASAS...COPPERAS COVE...
GATESVILLE...KILLEEN...TEMPLE...FORT HOOD...WACO
256 PM CST WED JAN 23 2008
...WINTER STORM WATCH IN EFFECT FROM LATE THURSDAY NIGHT THROUGH
FRIDAY MORNING...

THE NATIONAL WEATHER SERVICE IN FORT WORTH HAS ISSUED A WINTER
STORM WATCH...WHICH IS IN EFFECT FROM LATE THURSDAY NIGHT THROUGH
FRIDAY MORNING.

SLEET CHANGING TO FREEZING RAIN EXPECTED LATE THURSDAY NIGHT
THROUGH FRIDAY NOON ALONG AND WEST OF A LINE FROM
SHERMAN...MESQUITE...WACO...TO TEMPLE.

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.

$$


SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
304 PM CST WED JAN 23 2008

TXZ094-095-105>107-121>123-135-146>148-160>162-174-175-240500-
FANNIN-LAMAR-HUNT-DELTA-HOPKINS-KAUFMAN-VAN ZANDT-RAINS-HENDERSON-
NAVARRO-FREESTONE-ANDERSON-FALLS-LIMESTONE-LEON-MILAM-ROBERTSON-
INCLUDING THE CITIES OF...BONHAM...PARIS...GREENVILLE...
COMMERCE...COOPER...SULPHUR SPRINGS...TERRELL...KAUFMAN...
FORNEY...WILLS POINT...CANTON...GRAND SALINE...VAN...EDGEWOOD...
EMORY...POINT...EAST TAWAKONI...ATHENS...GUN BARREL CITY...
CORSICANA...TEAGUE...FAIRFIELD...PALESTINE...MARLIN...MEXIA...
GROESBECK...BUFFALO...CENTERVILLE...JEWETT...OAKWOOD...CAMERON...
ROCKDALE...HEARNE...FRANKLIN...CALVERT
304 PM CST WED JAN 23 2008
...FREEZING RAIN POSSIBLE FRIDAY MORNING...

A REINFORCING COLD FRONT WILL MOVE THROUGH NORTH TEXAS TONIGHT.
TEMPERATES FRIDAY MORNING WILL BE AT OR BELOW FREEZING ACROSS
NORTH TEXAS. PRECIPITATION WILL DEVELOP ACROSS WESTERN PORTIONS OF
THE AREA OVERNIGHT THURSDAY AND BEGIN TO MOVE EASTWARDS FRIDAY
MORNING. FREEZING RAIN MAY BE POSSIBLE EAST OF A LINE FROM
SHERMAN...MESQUITE...WACO TO TEMPLE. AT THIS TIME ICE ACCUMULATIONS
FRIDAY MORNING APPEAR TO BE RATHER LIGHT. HOWEVER...LITTLE ICE
ACCUMULATIONS WILL STILL CAUSE TRAVEL PROBLEMS AS A GLAZE WILL
FORM ON BRIDGES AND OVERPASSES. IF FUTURE DATA SUPPORTS GREATER
ACCUMULATIONS OF ICE A WINTER STORM WATCH...WARNING OR ADVISORY MAY
BE NEEDED.

STAY TUNED TO NOAA WEATHER RADIO OR http://WWW.WEATHER.GOV/FORTWORTH FOR
THE LATEST INFORMATION.

$$

85/HAMPSHIRE

http://forecast.weather.gov/wwamap/wwat ... 0statement

Be safe out there.

I was checking the local forecast for my area, and it's a 40% chance that the residents in the immediate DFW area are gonna get it.

[TexasStooge]

Travel Trouble Spots:

DALLAS/FORT WORTH
Friday: 41°F/37°F
__________________________________________________________________________________________

AMARILLO
Thursday: 34°F/24°F
Friday: 49°F/29°F
__________________________________________________________________________________________

LUBBOCK
Thursday: 31°F/25°F
Friday: 50°F/30°F
__________________________________________________________________________________________

WICHITA FALLS
Thursday Night: 28°F
Friday: 34°F/33°F
__________________________________________________________________________________________

ABILENE
Thursday: 34°F/28°F
Friday: 46°F/36°F

[jasons2k]

From last Wednesday:

It's very typical for the GFS and most models to have a hard time with the cold air. They'll show it initially, then lose it for several days in the 3-8-day timeframe, only to bring it back at the last minute.

We will likely have W or SW flow aloft, which would mean the airmass would be very shallow. It also would create a setup for overrunning precip. This is the kind of setup that historically brings winter weather to Texas. A lot will depend on exactly how much arctic air can be tapped. The setup does not, however, look like a massive dome of bitter cold.

At this point I would look for a winter weather threat for the Panhandle/W TX and North Texas, maybe as far south as central Texas and the Hill Country. A few days ago my best guess was a threat generally north of an Austin to Tyler line, and for now that still seems reasonable...assuming this all pans out.

I don't toot my own horn often, but I'm pretty pleased with how this one is working out. Not bad for a week+ away

[wall_cloud]

The PoP forecasts really don't match up well with the advisories. Advisories, by definition, mean that there is an 80% probability of the advisory criteria being met. Doesn't really jive well with 40/50 PoPs. While it may very well be a good advisory, the consistency is lacking. Either don't issue the advisory or increase the PoPs.

[gboudx]

The PoP forecasts really don't match up well with the advisories. Advisories, by definition, mean that there is an 80% probability of the advisory criteria being met. Doesn't really jive well with 40/50 PoPs. While it may very well be a good advisory, the consistency is lacking. Either don't issue the advisory or increase the PoPs.

The PoP for most of the DFW area is 70% Wintry Precip on Friday.

Thursday Night: A chance of freezing rain and sleet after midnight. Cloudy, with a low around 30. North northeast wind around 10 mph becoming east southeast. Chance of precipitation is 30%. Little or no snow accumulation expected.

Friday: Freezing rain likely before noon, then rain likely. Cloudy, with a high near 35. Southeast wind around 10 mph. Chance of precipitation is 70%.

[wall_cloud]

still not 80

[Portastorm]

From last Wednesday:

It's very typical for the GFS and most models to have a hard time with the cold air. They'll show it initially, then lose it for several days in the 3-8-day timeframe, only to bring it back at the last minute.

We will likely have W or SW flow aloft, which would mean the airmass would be very shallow. It also would create a setup for overrunning precip. This is the kind of setup that historically brings winter weather to Texas. A lot will depend on exactly how much arctic air can be tapped. The setup does not, however, look like a massive dome of bitter cold.

At this point I would look for a winter weather threat for the Panhandle/W TX and North Texas, maybe as far south as central Texas and the Hill Country. A few days ago my best guess was a threat generally north of an Austin to Tyler line, and for now that still seems reasonable...assuming this all pans out.

I don't toot my own horn often, but I'm pretty pleased with how this one is working out. Not bad for a week+ away

Yep, kudos are in order for you Jason ... nice call that far out!

[gboudx]

Close enough I guess. But you know how this goes in this part of the country; let's just wait and see. Could turn out to be all rain, all sleet or nothing at all. I'll wait for the eyewitness forecast.

[Ed Mahmoud]

0Z WRF predicted a 6 pm temp of 8.7ºC in ABI, actual temp was 6º. But even knocking 3º off the Friday predicted temps, it would still be above freezing when the very light precip fell. Similar error for SPS, but again even a flat subtraction (which is probably a gross over-simplification, but all I can think of doing) also has SPS above freezing.


3.9ºC above the 10ºC actual at Midland, and then simple subtraction would knock them below freezing on the WRF forecast when less than a tenth of precip was falling.



Qunatity of precip the WRF predicts would produce a disappointing winter storm in most of the WSW area.

[wall_cloud]

Close enough I guess. But you know how this goes in this part of the country; let's just wait and see. Could turn out to be all rain, all sleet or nothing at all. I'll wait for the eyewitness forecast.

That's why the 80% is in the directive...so you don't have to wait and see.

[Ed Mahmoud]

I'm just glad I got to be outside during freezing drizzle near Kadane Corner, TX. If it doesn't ice here in Houston, I have had my exposure to at least the lowest form of winter weather fun.

[Ed Mahmoud]

No thunder, but the rain coming down pretty good at Maisson du Ed, and a clap of thunder wouldn't surprise me.

[wall_cloud]

I totally read those watches wrong. I initially thought they were advisories. Watches are ok with 50% or great PoPs. Advisories and warnings require 80%. Please excuse my idiocy.

[jasons2k]

Latest from Jeff Lindner:

Lovely weather this week continues for the next 48 hours…then some improvements.

Winter Storm Watches issued along the I-35 corridor from Temple to DFW to Paris TX where freezing rain/icing is likely tonight.

Disco:

Active sub-tropical flow with multiple embedded impulse continues to produce widespread rains across the region this morning. Next batch of heavier rain just E of KSAT and moving eastward at around 30mph…should be reaching SE TX western counties in the next 2 hours and Houston metro around late morning. Surface cold dome has been re-enforced this morning by a secondary surge of cold air from the north. Upstream dewpoints have fallen into the teens and 20’s over N TX and some of this drier air will move southward resulting in rain chances lessening N of I-10 this afternoon and evening…have no fear the rain returns with a vengeance on Friday.

Expect sub-freezing temps. to remain N of our area tonight keeping the icing and freezing rain headaches from around Temple N through the DFW area and then western across WC TX. Could see accumulations of 1/4th to 1/3rd of an inch of glazing through noon Friday so needless to say travel will be difficult both on the roads and in the air.

Locally, a break in the rain this evening will end early Friday as stronger impulse comes out of Mexico and forms a coastal low off of Brownville which moves up the coast Friday and Friday night. Expect widespread rains to develop during the day and push inland as shallow cold dome is heavily overrun by Gulf moisture. Surface warm front will also surge northward reaching the coast late Friday night with more convective type showers and heavier rainfall rates.

Hydro:

Grounds are saturated across the area from the two systems last week and off and on rains this week. The San Bernard River is running around flood stage East Bernard and Boling and West Mustang Creek is running above action stage at Ganado. Additional basin rainfall amounts of 1-2 inches over the next 48 hours will help bring these systems even higher…possibly exceeding their flood stages. Will need to also keep an eye on the Tres Palacios River near Midfield as it is currently running just below action stage and tends to respond rapidly to heavy rains. Elsewhere most basins should be able to handle the expected rain amounts…although there may be ponding in urban areas where the rain falls quickly.

Temps. will go nowhere for the next 48 hours as they remain nearly steady in the upper 30’s and lower 40’s across the area with gusty NE winds. Warm front will push through the area on Saturday and temps. will quickly warm as arctic dome is erode and its surface high wedge is pushed off to the east. Expect highs to warm into the 70’s by early next week and lows to recover into the 60’s under good southerly flow…our lows will be about 25 degrees higher than our current highs today and Friday…how about that for a warming trend. Rain chances will lower this weekend only to return early next week as the next storm system approaches the region.

[gboudx]

Another Jeff Lidner email:

Winter Storm Watch issued along and W of a line from Temple to Paris including all of the Dallas/Fort Worth metro areas.



Freezing rain and icing likely tonight with significant travel problems for Friday morning.



Discussion:



Cold arctic surge has overspread all of N TX this morning with temps. near freezing in many areas and gusty N winds. Dewpoints have fallen into the teens areawide. Noisy sub-tropical flow with strong impulse off of Baja will eject across TX tonight. Impressive warm air advection regime will begin as Gulf moisture is pulled northward over the near freezing surface cold dome resulting in gradual ascent of the moist air mass above the cold surface air…isentropic lifting. It will take several hours to moisten the low layer enough for precip to reach the ground…however once the atmosphere reaches that point rain will begin to fall. With such low dewpoints in place the falling rain will at first evaporate as it fall toward the surface lowering the air temp toward the dewpoint while the dewpoint rising toward the air temp…until the near surface layer is saturated…wet bulb cooling.



Temps. will recover very little today under clouds and cold air advection…likely peaking in the mid to upper 30’s. As isentropic processes begin this evening the cloud bases will lower and light rain will break out from the SW to the NE while surface temps. are wet bulbed to freezing and below. Icing will begin out W and SW this evening and overspread all of the area after midnight. Expect elevated surface to glaze first…power lines, trees, overpasses, and highway flyovers. By Friday AM with several hours of freezing rain having occurred expect surface streets to ice over along with highway mainlanes.



Current expected ice accumulations to range from 1/10th of an inch at the SE edge of the Watch area to over 1/3rd of an inch over the NW part of the watch area. For the DFW area accumulations of 1/10th to 1/4th of an inch of ice look likely. Needless to say significant disruption in travel is likely after midnight tonight through about noon on Friday. It does not appear at this time enough glazing will occur to result in power line failures…this is more a surface and air travel concern icing event.



Will reassess this afternoon and may fire off another e-mail if any big changes look likely and new model data comes in.

[gboudx]

DFW AFD update

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
1118 AM CST THU JAN 24 2008

.UPDATE...
CURRENT WINTER WEATHER WATCH STILL LOOKS REASONABLE. A CERTAIN AREA
OF NTX MAY REQUIRE A WINTER WEATHER WARNING FOR THE OVERNIGHT/FRIDAY
MORNING PERIOD WHILE OTHER LOCATIONS TRANSITION TO AN ADVISORY. THIS
WILL BE DISCUSSED IN HOUSE AT NOON TIME WITH A BATCH OF NEW PRODUCTS
ISSUED WITH THE AFTERNOON PACKAGE.

MORNING MODELS HAVE NOT CHANGED VERY MUCH. GFS KEEPS PRECIP AXIS
FURTHER NORTH THAN NAM/NGM/ECMWF. 12Z MOS TEMPS HAVE TRENDED UP
SLIGHTLY...BUT WE STILL FEEL THAT WET BULB COOLING IS NOT BEING
TAKEN INTO ACCOUNT (LOWEST 50-100 MB) BY THESE ANY MODELS. 75

I'm guessing this Warning area would be the NW counties of the metroplex, and the Advisory being SE of there, including the DFW counties.

[CaptinCrunch]

DFW AFD update

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
1118 AM CST THU JAN 24 2008

.UPDATE...
CURRENT WINTER WEATHER WATCH STILL LOOKS REASONABLE. A CERTAIN AREA
OF NTX MAY REQUIRE A WINTER WEATHER WARNING FOR THE OVERNIGHT/FRIDAY
MORNING PERIOD WHILE OTHER LOCATIONS TRANSITION TO AN ADVISORY. THIS
WILL BE DISCUSSED IN HOUSE AT NOON TIME WITH A BATCH OF NEW PRODUCTS
ISSUED WITH THE AFTERNOON PACKAGE.

MORNING MODELS HAVE NOT CHANGED VERY MUCH. GFS KEEPS PRECIP AXIS
FURTHER NORTH THAN NAM/NGM/ECMWF. 12Z MOS TEMPS HAVE TRENDED UP
SLIGHTLY...BUT WE STILL FEEL THAT WET BULB COOLING IS NOT BEING
TAKEN INTO ACCOUNT (LOWEST 50-100 MB) BY THESE ANY MODELS. 75

I'm guessing this Warning area would be the NW counties of the metroplex, and the Advisory being SE of there, including the DFW counties.

I say it will be for the counties to the South and SE of the DFW. Models have not handled the cold air at all over the past 2 weeks, so I will go with a 5 degree less difference than forecasted. I also believe precip will start off as frz rain and continue to fall as frz rain thur friday morning. Highs will not warm as much on friday if we get enough ice, as it will keep temps lower than forecasted and with cloud cover temps may stay around the freezing mark or just above (31-33)

It may only be a 1 day ice event but I would not rule out the possibilty of it being a major event. Either way driving will be a nightmare in the morning.

FYI: Hoping for a 3 day weekend

TEMPERATURES ARE DEPENDENT ON QPF PLACEMENT DUE TO SUBSTANTIAL
EVAPORATIVE COOLING EXPECTED WITH MODELS TOO MOIST WITH SFC
DEWPOINTS BEFORE RAIN BEGINS. ALTHOUGH SURFACE LAYER IS VERY
DRY...DRY LAYER IS ALSO VERY SHALLOW...WITH ONSET OF PRECIPITATION
EXPECTED SOON AFTER ISENTROPIC ASCENT BEGINS. FOR NOW HAVE GONE
CONSERVATIVE...BUT THERE IS A DISTINCT POSSIBILITY OF FZRA BEGINNING
SOONER THAN 10Z FOR METROPLEX SITES.

[TxWxFrisco]

Frisco, Tx. (North of Dalls)

2:00pm

43.5 F Temp
15.6 F Dewpoint

Lots of room for evaporative cooling...

[gboudx]

Think there's anyway there's enough evaporative cooling for sleet instead of freezing rain?

I remember last year we were supposed to have some freezing rain, but the rain was so heavy that it transported warmer temps in the upper layers down to the surface, so the DFW area never got to freezing. The point of this rambling is that it seems like anything can happen once the players reveal themselves in real-time.

[CaptinCrunch]

Think there's anyway there's enough evaporative cooling for sleet instead of freezing rain?

I remember last year we were supposed to have some freezing rain, but the rain was so heavy that it transported warmer temps in the upper layers down to the surface, so the DFW area never got to freezing. The point of this rambling is that it seems like anything can happen once the players reveal themselves in real-time.

Dew points are lower and the rain will not be as heavy, but more of a shower lasting for a longer period of time. Plus we have been in a colder phase the past few weeks with the last couple of arctic fronts pushing thru. I expect lows across DFW will range in the 27-30 degree area with the heavest icing from a line of Commanche to Ft Worth, to Sherman and North and West of there, with less icing to the East and SE.