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New meso discussion being issued. Will update shortly.

MESOSCALE DISCUSSION 0170
NWS STORM PREDICTION CENTER NORMAN OK
0923 PM CST MON MAR 03 2014

AREAS AFFECTED...S-CNTRL AND SE TX

CONCERNING...FREEZING RAIN

VALID 040323Z - 040830Z

SUMMARY...FREEZING RAIN THREAT WILL EXPAND SPATIALLY THROUGH LATE
EVENING AND EARLY TUE MORNING ACROSS S-CNTRL AND SE TX. RATES OF
0.05-0.1 INCH/HR WILL BE COMMON...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE IN ASSOCIATION WITH THUNDERSTORMS.

DISCUSSION...SWATH OF CONVECTION EXTENDING FROM THE SRN HILL COUNTRY
EWD ALONG I-10 TO JUST W OF HOU APPEARS TO HAVE INITIATED IN
RESPONSE TO A WEAK UPPER IMPULSE OVER THE CENTRAL TX COAST /AS OF
03Z/...AND STRENGTHENING WAA REGIME ABOVE 2.5 KM AGL PRECEDING A
STRONGER VORT MAX APPROACHING THE BIG BEND. THIS IS OCCURRING MUCH
EARLIER THAN A MAJORITY OF 12Z/00Z MODEL GUIDANCE HAS
FORECAST...WITH EXCEPTION TO THE 12Z WRF-NSSL AND WRF-NMM
RUNS...WHICH APPEAR TO HAVE A SOMEWHAT REASONABLE DEPICTION OF
ONGOING ACTIVITY BUT ARE STILL SLOW WITH RESPECT TO OBSERVATIONS.

SFC OBS INDICATE TEMPERATURES ARE GENERALLY NEAR/ABOVE FREEZING
WHERE PRECIPITATION IS ONGOING CURRENTLY...WITH SFC FREEZING LINE
ANALYZED FROM NEAR TPL SEWD TO 20 N HOU AS OF 03Z. COMBINATION OF
WET-BULB COOLING /VIA ELEVATED CONVECTIVE PRECIPITATION FALLING INTO
RELATIVELY DRIER SUB-CLOUD LAYER/...AND MODEST LOW-LEVEL CAA OUT OF
THE N/NE...SHOULD RESULT IN TEMPERATURES FALLING BELOW FREEZING OVER
THE NEXT 2-3 HRS ACROSS THE REGION. THIS WILL OCCUR
CONTEMPORANEOUSLY WITH A CONTINUED INCREASE IN FORCING FOR ASCENT AS
THE AFOREMENTIONED SHORTWAVE IMPULSE MOVES OUT OF THE BIG BEND...AND
FACILITATES AN INCREASE IN PRECIPITATION COVERAGE OVER THE NEXT
SEVERAL HRS. OBSERVATIONAL TRENDS SUGGEST THE GREATEST THREAT FOR
FREEZING RAIN APPEARS TO BE FOCUSED NEAR/N OF THE I-10 CORRIDOR FROM
THE SRN HILL COUNTRY TOWARDS HOU.

..ROGERS.. 03/04/2014


ATTN...WFO...LCH...HGX...FWD...EWX...

I am thinking around 11 or so, closings "might" be initiated. They may wait until 4-5 am though also. I agree with biff given the past few events didn't produce as intended, they may be a little skeptical to close down schools, business, courts and etc. I am a little curious though that now the warnings are issued, why nobody has really made a statement. I can only guess the city is watching these bands heading in and are waiting to see what they drop before making the call.

EWX update: 912 PM CST MON MAR 3 2014

.UPDATE...
ADDED BANDERA AND MEDINA COUNTIES TO THE WINTER WEATHER ADVISORY
DUE TO POTENTIAL FOR SLEET FROM CONVECTION WHICH WOULD RESULT IN BRIEF
HEAVIER ACCUMULATIONS ON ROADS...ESPECIALLY AT THE HIGHER
ELEVATIONS OF THOSE COUNTIES. TEMPERATURES WERE AT FREEZING
ACROSS EASTERN WILLIAMSON...TRAVIS INTO LEE AND BASTROP COUNTIES
AT 9 PM...AND APPROACHING FREEZING ACROSS THE HILL COUNTRY AND NRN
SECTIONS OF S CENTRAL TX. ALTHOUGH COLD AIR ADVECTION IS WEAK...
EVAPORATIVE COOLING HAS ACCELERATED COOLING INTO THE MID 30S IN
LOCALIZED AREAS. HAVE ADDED MORE THUNDER/SLEET TO FORECAST FOR
TONIGHT IN ADDITION TO THE FREEZING RAIN. ONGOING ADVISORY AND
WINTER STORM AREAS LOOK GOOD FOR NOW WITH THE ADDITION OF BANDERA
AND MEDINA COUNTIES. WILL LET SHORT TERM FORECAST/SPECIAL WEATHER
STATENTS HANDLE MENTION OF SMALL ONE HALF INCH HAIL IN THE
ISOLATED STRONGER CELLS.

AFTER THIS INITIAL WAVE OF CONVECTION AHEAD OF THE UPPER
TROUGH...STILL EXPECT ANOTHER ROUND OF ELEVATED CONVECTION AFTER
MIDNIGHT WITH TEMPERATURES LOWERING TO AT OR BELOW FREEZING
ACROSS THE WARNING AND ADVISORY AREAS.

Rain starting to fall in Kingwood. Temps is 32

Anyone have any reports out of NW Harris, Waller or Austin county area? Radar is showing some decent precip up there right now!

Well, that answers my question/concern from earlier. Gonna be a long night!

raining in Willowbrook. My thermometer is reading 36.

This is a dangerous situation folks, and possibly not just for bridges and elevated surfaces. Ground temps will have cooled significantly from the low maximum temperatures we had throughout the day. The effect of those 80s yesterday afternoon is getting more diffuse the longer the cold stays in place.

I think the NWS made a solid move pulling the trigger early with warnings for Harris county.

I imagine the schools around the area are going to wait until something actually happens

A steady moderate rain falling here now. 35 degrees.

That red blob to the southwest of Houston looks like a severe cell making a b-line for the city. Is that going to hold up?

Getting some good lighting in kingwood

Lightning to my SW just now. Light freezing rain has started in NW Harris County. Temp down to 31F.

Rain, Lightning, and Thunder in Kingwood - Temperature at 30

Mr. T wrote:Rain starting to fall in Kingwood. Temps is 32

Let's see what effects is has on the temp there. Will it be evaporative cooling or will the moisture pull the upper warm layer down and mix to warm the surface?

Hearing some faint thunder now...

Thundering here too, wow.

I JUST HAD A STROKE OF LIGHTNING CG BOLT

Getting lightning and thunder here in humble!

davidiowx wrote:Anyone have any reports out of NW Harris, Waller or Austin county area? Radar is showing some decent precip up there right now!

I just started getting sprinkles here in my area of NW Harris....just sprinkles though.

Edit: OMG, wow. It started THUNDERING 5 seconds ago....oh my......caught me off guard.