Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Fort Worth Texas
1140 PM CDT Wednesday Jul 23 2014
concerns...brief MVFR visible /5sm br/ for kact in the morning.
Storms are dying for the night and do not expect any more to
affect the terminals during this forecast. Any thunderstorms and rain on Thursday
afternoon/evening should be east of the terminals and might affect
some inbounds from the east.
Expecting 5sm br at kact 10-13z...otherwise VFR conditions /few-
sct060 and broken- sct250/ at all sites the rest of the forecast.
Winds becoming light east to southeast overnight with southeast
5-10 knots on Thursday. 75
the complex of storms that rolled across the eastern zones late
this afternoon/evening continues to weaken with the loss of
surface heating. The complex did throw out an impressive outflow
which currently resides near the i35/35w corridor. The outflow
continues to weaken but still probably has some wind gusts in
excess of 30 miles per hour. Lift along the outflow will continue to
generate a few showers and thunderstorms through the evening...
but the loss of heating and the large scale subsidence over the
region should keep activity isolated at best.
For this update will remove all counties in both severe
thunderstorm watches. Will adjust probability of precipitation down for all counties
except the far eastern zones. Will also lower overnight lows in
the northeast/east zones due to cooler temperatures within the storm
Previous discussion... /issued 243 PM CDT Wednesday Jul 23 2014/
thunderstorms have begun to develop northeast of the region in
proximity of a weak cold front and Stout shortwave. Model trends
indicate that convection will be on the increase to our
northeast...with the northeast flow regime driving this activity
southwestward toward North Texas. At the current rate of
development and movement...convection should begin to cross over
into Lamar County near Paris and surrounding areas around 6 PM or
so. The time of day would suggest that some of these storms will
be strong to possible severe...with damaging winds being the main
threat as they affect the northeastern counties. A weakening
trend is expected as cells move farther southwest...due to the
waning of surface heating and also to the increasing subsidence
from the dominant ridge to the west. Still...low probability of precipitation will be
maintained in the metroplex and surrounding areas through midnight
or so....with activity dissipating thereafter.
A low chance of thunderstorms will arise again Thursday as a weak
front sags south to near the I-20 corridor...providing focus for
isolated development...mainly in the afternoon. West of I-35...it
appears that subsidence from the upper ridge will shut off any
attempt for convective development.
The primary weather concern over the next few days will be the
increasing temperatures and uncomfortable heat. After carefully
running and finalizing the temperature/dewpoint forecast...the
resulting apparent temperature grids are indicating heat indices
fairly widespread in the 105 to 108 degree range both Thursday afternoon
and Friday afternoon. The only exception to this is the
southwestern counties where drier conditions should keep the heat
index below 105. We will go ahead and include a heat advisory for
most of North Texas...excluding the areas west of a Mineral Wells
to Gatesville line where conditions should remain below criteria.
The advisory will be in effect from noon Thursday until 9 PM
Friday night. Please use caution when participating in outdoor
activities...stay hydrated...and schedule strenuous activities for
early in the day when possible.
The weather pattern will begin to shift on Monday...as an upper
trough deepens over the eastern states and the upper ridge slides
to the west. This will place North Texas in a strong north to
northwest flow regime. This pattern will send another rare July
cold front south from the plains across the Red River on Monday. A
chance of rain can be expected Monday and Tuesday associated with
the front....with cooler conditions expected for most of next week
behind the front.
Preliminary point temps/pops...
Dallas-ft. Worth, Texas 78 100 80 103 79 / 20 10 10 5 0
Waco, Texas 74 100 77 101 76 / 20 10 10 5 0
Paris, Texas 69 95 73 99 75 / 40 20 10 5 0
Denton, Texas 76 100 77 103 78 / 20 10 10 5 0
McKinney, Texas 74 98 77 102 77 / 20 10 10 5 0
Dallas, Texas 77 100 80 103 78 / 20 10 10 5 0
Terrell, Texas 73 99 76 101 76 / 40 10 10 5 0
Corsicana, Texas 73 99 77 100 76 / 20 10 10 5 0
Temple, Texas 74 99 76 100 76 / 20 10 10 5 0
Mineral Wells, Texas 75 101 76 103 76 / 20 10 10 5 0
heat advisory from noon Thursday to 10 PM CDT Friday for