Area Forecast Discussion
Issued by NWS Dallas/Fort Worth, TX
FXUS64 KFWD 191227 AAA
Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
727 AM CDT TUE JUL 19 2016
It still appears the proximity of the mid-level ridge should
limit shower/thunderstorm development. Chances are far too low
along the I-35 corridor to mention in any TAFs, but any activity
in East Texas this afternoon could result in some in-flight
impacts. Otherwise...persistence forecast with daytime CU and
light S/SE winds.
.PREV DISCUSSION... /ISSUED 303 AM CDT TUE JUL 19 2016/
A broad ridge of high pressure was anchored from the central/
southern High Plains eastward all the way into the Deep South
early this morning. This pattern is relatively normal for this
time of the year. Mid level heights near the center of the upper
high will be pushing 600 decameters, as the high center remains
anchored over Kansas/Oklahoma the remainder of the week. High
temperatures ranging from the mid 90s to around the century mark
will be prevalent through Wednesday.
Water vapor satellite imagery does depict some moisture trapped
within the ridge across the southeast half of the CWA today and we
tend to call these types of upper highs a `dirty ridge`. A few
diurnal showers and thunderstorms may develop within the better
moist axis across the far east-southeastern counties late this
afternoon and early evening before nightfall. With lapse rates
aloft being minimal, we do not expect activity to persist long in
one place or be strong to severe.
The core of the upper high will strengthen and expand mid-late
week and suspect many areas will hit the century mark for the
first time by Thursday, with similar dry and hot conditions
maintaining into the coming weekend. If there is a plus side to
the heat, it will be that deep mixing will help mix surface dew
point temperatures down enough to keep afternoon heat index
values relatively close to the actual ambient high temperatures.
The only concern for higher heat index values later this week will
be those areas east of the I-35E/I-45 corridors where denser
vegetation and evapotranspiration should help keep surface dew
points up a little higher with heat index values hovering around
105 degrees from Thursday into the weekend.
It appears a weakening of the broad upper level high pressure
dome occurs early next week, as a vigorous shortwave trough
transverses across the Northern Plains and into the Great Lakes.
The European model is stronger with this feature than the GFS with
regard to how much this degrades the upper high over the Southern
Plains and Lower Mississippi Valley. Either way, there will be an
increase in moisture contained within easterly low-mid level flow
along the southern periphery of the upper high over North and
Central Texas. Slight chances for showers and thunderstorms have
been maintained for the first half of next week, though overall
confidence remains low regarding the mid level pattern changes.
.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth 96 78 99 78 100 / 5 5 0 0 0
Waco 98 77 99 77 100 / 5 5 0 0 0
Paris 96 76 97 76 99 / 20 10 10 5 0
Denton 95 75 97 75 99 / 5 5 0 0 0
McKinney 95 76 97 76 99 / 10 5 5 0 0
Dallas 96 78 98 78 100 / 5 5 0 0 0
Terrell 95 76 97 76 100 / 10 5 5 5 0
Corsicana 96 77 97 77 100 / 10 5 5 5 0
Temple 98 75 98 75 100 / 5 5 0 0 0
Mineral Wells 97 74 98 74 100 / 0 5 0 0 0