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Area forecast discussion 
National Weather Service Fort Worth Texas
1206 PM CDT Tuesday Aug 30 2016

a bit of a quieter start to the day today, with a similar forecast
for the afternoon and evening. In the next few hours, do expect to
see scattered convection to start to impact the airspace once
again. The cumulus field isn't quite as active as yesterday, but
there is some vertical development. Will likely see the first hour
or so of the new taf to be VFR, with thunderstorms in the vicinity beginning around 19-20
UTC. Once again, most convection will diminish at or around
sunset, with only isolated activity overnight.



Previous discussion... /issued 408 am CDT Tuesday Aug 30 2016/
morning water vapor imagery shows an upper low spinning along the
Texas coast with a broad ridge centered over the mid-Mississippi
Valley. Another upper low is located along the Georgia/SC coast and
Tropical Depression Nine is still positioned just to the
northwest of Cuba. The position of all of these features will help
keep deep easterly flow in place along the northern Gulf Coast and
into North Texas through today. This will result in a continued
moist and unstable environment across the region with scattered
showers and thunderstorms remaining in the forecast.

Over the last hour...a few showers and thunderstorms have
developed across our eastern counties from Canton to just north of
Palestine. These are likely associated with one of many subtle
disturbances rotating around the slow moving upper low along the
coast. These little features provide just enough forcing for
ascent in the moist uncapped environment to trigger scattered
showers and storms and this trend is expected to continue through
the day with coverage increasing as we heat up. The one difference
that we have today versus yesterday is the position of the 500mb
ridge. This ridge axis is forecast to shift westward through the
day although its overall strength will weaken some as it does. In
theory this should result in an increase in subsidence as the
ridge shifts westward...however most of the high resolution
guidance develops convection across a good chunk of North Texas
with highest coverage in the northeast counties closer to the
approaching ridge axis. There does appear to be a surge of mid
level moisture that approaches from the east later today and the
guidance could be suggesting that subsidence won't be an issue in
getting thunderstorms to develop. Either way...given the amount of
moisture that we already have and the fact that there should at
least be some lift from the nearby upper low...will keep rain
chances at 20-30% across the entire area. Locally heavy rainfall
and gusty winds will continue to be the main threats.

By tomorrow...we should see a marked decrease in coverage of
thunderstorms as the weak upper low continues to slowly move south
and the center of the ridge axis is nearly overhead. A cold front
will be moving through the Southern Plains during the day and
approaching our northwest counties by evening. This will likely be
sufficient for some scattered thunderstorms during the late
afternoon/evening across our northwest counties. The frontal
boundary will be in our area on Thursday with rain/storm chances
going up areawide during peak heating. This will continue into
Friday before some drier air begins to move in from the northeast.

Rain chances appear to be fairly low for the upcoming weekend into
early next week. Temperatures will be slightly below normal today
with the expected convection and associated cloud cover then warm
back into the low/mid 90s for tomorrow.



Preliminary point temps/pops...
Dallas-ft. Worth 92 77 95 77 93 / 30 10 10 20 40
Waco 90 75 93 75 93 / 30 20 10 10 20
Paris 90 73 94 73 88 / 20 10 10 20 40
Denton 91 72 93 72 90 / 20 10 20 20 40
McKinney 90 73 93 74 90 / 20 10 10 20 40
Dallas 93 78 95 78 92 / 30 10 10 20 40
Terrell 91 74 93 74 91 / 20 10 10 10 40
Corsicana 91 76 94 76 92 / 30 10 10 10 30
Temple 89 73 93 73 93 / 30 20 10 10 20
Mineral Wells 91 71 92 72 90 / 30 20 20 20 40


Forward watches/warnings/advisories...



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