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Area forecast discussion...updated 
National Weather Service Fort Worth Texas
557 am CDT Tuesday Jul 22 2014

/12z tafs/

Thick cirrus continues to spread across North Texas this morning
but this will thin out over the next several hours. Widespread
MVFR visibilities around 5 miles are being reported mainly east of
the major airports. Ample low level moisture is in place across
the region and there could be a brief period where visibilities
drop to around 5 miles in the have added a tempo
for a couple of hours to include this. As of now...low stratus is
confined to areas well southeast of the major airports but there
is some chance that stratus could develop for a couple of hours
this morning. Think that this will mainly occur east of I-35 but
will have to watch over the next couple of hours. Otherwise...VFR
conditions expected through the remainder of the period.



Previous discussion... /issued 349 am CDT Tuesday Jul 22 2014/
water vapor shows the well advertised upper level anticyclone
gaining strength over eastern New Mexico...but also of interest is
a developing TUTT low centered over Mobile. 850mb analysis
depicts what could be argued as a cold front that is draped along
the Louisiana coastline to near Mobile. Latest satellite actually
confirms the presence of a low level convergence boundary
indicated by a band of clouds which begins across the Palestine
area and extends southeast to the Gulf Coast where vigorous
convection has developed overnight. Since this weak boundary
should hang across the southeast counties today...will maintain a
mention of isolated convection there this afternoon and evening.
Across the remainder of North Texas...strong subsidence from the
intensifying upper level high to our northwest and limited deep
layer moisture will ensure a dry and hot forecast.

Model guidance keeps low level thickness values nearly steady
through the next 2 to 3 expect highs to stay fairly
close to yesterday/S readings with just a slow daily warming
trend. Also dewpoints should mix out a few more degrees this the heat index should be a bit lower than Monday.

On Wednesday a shortwave trough will drop down the eastern fringe
of the upper high and through the Ozarks. There is good model
agreement that this will set off convection Wednesday afternoon
across Arkansas and eastern Oklahoma. With 30kt northeasterly flow
at 500mb...this activity will make a run at the County Warning Area Wednesday
evening. Most model guidance now indicates some quantitative precipitation forecast over the
northeast half of the County Warning Area Wednesday evening...and therefore will
maintain the forecast of 30 percent probability of precipitation in the northeast zones
tapering down to 20 percent or less farther to the southwest.

On Thursday the aforementioned TUTT low will move west and into
south Texas...providing some weak lift for an enhancement of
isolated diurnal convection. Moisture will be best for areas east
of I-35 and this is where 20 probability of precipitation will be advertised. Low level
moisture will be a little higher Thursday which will increase the
chance that heat index values will reach 105 for more locations.

The upper level high will begin to shift slightly eastward by
Friday and subsidence increases over the region...resulting in
further warming of low level thickness values. Highs should be
around 100 degrees for most of North Texas Friday into Sunday.
Dewpoints will likely remain high enough to put heat index values
in the 103 to 108 degree range during the afternoon. A heat
advisory will probably be required for some portion of the County Warning Area by
this time.

The upper level high will back off to the west by Monday as a
trough deepens over the eastern US. This will allow for a weak
cold front to move into the region early next week. Temperatures
should cool slightly...and the front may result in a slight chance
of rain Monday. With northwest flow aloft developing by Tuesday or
Wednesday of next is possible that our rain chances may
increase a bit more in 8 or 9 days...but no promises at this time.



Preliminary point temps/pops...
Dallas-ft. Worth, Texas 98 76 99 78 99 / 0 0 5 20 10
Waco, Texas 97 72 98 72 99 / 5 5 5 10 10
Paris, Texas 93 70 96 73 97 / 5 5 20 30 20
Denton, Texas 96 72 97 72 99 / 0 0 5 20 10
McKinney, Texas 96 71 97 73 99 / 0 0 10 30 20
Dallas, Texas 97 77 98 79 99 / 0 0 5 20 10
Terrell, Texas 96 73 98 74 99 / 5 5 10 20 20
Corsicana, Texas 95 72 97 74 98 / 5 5 10 20 20
Temple, Texas 97 72 98 71 99 / 5 5 5 10 10
Mineral Wells, Texas 99 72 100 72 100 / 0 0 5 10 10


Forward watches/warnings/advisories...



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