Area forecast discussion...updated
National Weather Service Fort Worth Texas
438 PM CDT Monday may 20 2013
Update...
increased probability of precipitation to likely from Comanche County northward into Young and
Jack counties. Also added hail and strong thunderstorm gusts to
the public forecast and hourly grids. 75
&&
Previous discussion... /issued 306 PM CDT Monday may 20 2013/
An active pattern will continue across the County Warning Area through Tuesday as
a deep upper low over South Dakota and Nebraska remains quasi-
stationary and a strong shortwave trough moves across our region
on Tuesday. After Tuesday...upper ridging develops over the
southern and central rockies and then moves east over the Great Plains
by the weekend. The return of northwest upper flow on Wednesday
should help to push a cold front down through Oklahoma and across
the Red River early Wednesday. This front and the northwest flow
aloft could result in some elevated convection Thursday night and
Friday morning.
Through this evening...the dryline has become active from south of
Wichita Falls through central Oklahoma. Although the cap is still
intact across the central and eastern part of our County Warning Area...we expect
it to weaken out west with storms developing southward through 5 PM.
Storm movement should be northeast but line propagation will push
them farther in our County Warning Area this evening and maybe to a Sherman to
Goldthwaite line by midnight. As stated earlier today...the
atmosphere is very unstable with large cape thus large hail (up to
baseball) and damaging winds (65mph+) are possible and expected.
Helicity will be the highest near the Red River 5 to 8pm...so
tornadoes are also possible. Some of the Oklahoma activity might
slide across the red after midnight and decided to keep high probability of precipitation
going for now.
Tuesday...convection should redevelop across Oklahoma on Tuesday
morning and propagate southeast across our County Warning Area. Several high-res
models indicate a squall line forming across Oklahoma by midday
and moving southeast across a good portion of the County Warning Area during the
afternoon. Also there could be several left over mesoscale
features that would enhance storm development. Rainfall might
exceed 1 1/2 inches in some areas...but do not feel flash flooding
will be a major concern due to guidance values of around 3 inches
in 3 hours.
Temperatures will remain rather seasonably warm and humid through
the period. However...if the cold front ends up being stronger than
expected or penetrates farther south...then the drier air would
allow slightly cooler lows Wednesday-Friday over the northern half than
what is currently being forecast. 75
&&
Preliminary point temps/pops...
Dallas-ft. Worth, Texas 71 86 65 88 69 / 30 60 40 10 10
Waco, Texas 72 89 67 89 70 / 10 60 60 10 10
Paris, Texas 69 81 63 85 64 / 60 70 40 10 10
Denton, Texas 69 85 62 88 65 / 40 50 20 10 10
McKinney, Texas 70 84 64 88 65 / 40 70 30 10 10
Dallas, Texas 72 86 69 89 72 / 30 60 40 10 10
Terrell, Texas 71 86 67 88 69 / 30 70 60 10 10
Corsicana, Texas 72 87 70 88 70 / 10 60 70 10 10
Temple, Texas 72 88 68 88 69 / 10 50 60 10 10
Mineral Wells, Texas 68 87 61 89 66 / 30 50 20 10 10
&&
Forward watches/warnings/advisories...
none.
&&
$$
/75
