289
FXUS64 KFWD 161027
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
527 AM CDT Tue Jul 16 2024

...New Aviation, Short Term...

.SHORT TERM... /NEW/
Update:

No changes to the forecast through Wednesday other than to
slightly adjust timing of rain chances into the late afternoon.
Otherwise it will be hot today with highs just above 100 degrees
and heat indices near 105.

Dunn

Previous Discussion:
/Overnight through Wednesday/

Clear skies and a steady south wind will result in a warm but
quiet night tonight as temperatures fall into the upper 70s by
morning. Persistent ridging will remain in place on Tuesday with
North Texas firmly beneath the eastern periphery resulting in hot
and dry conditions. Modest south-southwesterly flow beneath the
subsident ridge along with strong afternoon heating has promoted
deep mixing the last several afternoons. This should continue on
Wednesday with dewpoints falling into the mid 60s during peak
heating. This reduction in RH should result in heat indices at or
just above the actual air temperature. With high temperatures
forecast to be in the upper 90s to near 103 today, we`ll see a few
locations meet Heat Advisory criteria this afternoon. The current
advisory covers this well, and no changes are anticipated at this
time.

Today will be the hottest day this week as we undergo a pattern
change through the end of the week which will certainly be
welcome this time of year. Troughing will amplify over the
Northern Plains and Great Lakes this afternoon into Wednesday
allowing a chunk of cooler Canadian air to slide southward
through the Plains while pushing our mid level ridge westward.
While summertime cold fronts are generally a rare treat, this one
will be aided southward by a rather potent surface high pressure
center around 1024 mb which represents an approximate 6-8 mb
positive anomaly. This suggests that the front shouldn`t have any
trouble making it into North Texas, and much of the high
resolution guidance now shows the front crossing the Red River on
Wednesday afternoon. Given an earlier arrival during peak heating,
we`ll likely see scattered afternoon showers and thunderstorms
develop along the boundary and have raised PoPs accordingly. It`s
a little uncertain how much heating we`ll see ahead of the front,
but typically we have no problem warming up, and for now we`ll
keep high temperatures in the upper 90s, but there is potential
for these to need to be lowered. Given the timing of the
thunderstorm chances, there will be a threat for strong storms
with primarily a damaging wind threat through the afternoon.

Dunn

&&

.LONG TERM... /Issued 355 AM CDT Tue Jul 16 2024/
/Thursday Through the Early Next Week/

The extended portion of the forecast will be dominated by an
unusual pattern for July: persistent northerly flow into Texas,
which will be sandwiched between a strongly amplified ridge in the
West and a Bermuda high to the east. This will maintain below
normal temperatures and above normal rain chances.

The cold front mentioned in the short term portion of the forecast
may take its time clearing Central and East Texas on Thursday,
keeping considerable shower/thunderstorm chances in place.
Evacuating low-level moisture will reduce the instability, and
generally weak shear should assure rather disorganized convection
with a minimal threat for strong storms. The frontal boundary will
then retreat, potentially maintaining its resolution enough to
serve as a focus for redevelopment on Friday. Even where the
boundary isn`t involved, surface heating and the absence of
inhibition may allow for scattered afternoon convection,
particularly across Central Texas where the moisture return will
occur first. A similar day will follow on Saturday with sunshine-
buoyed temperatures reaching the mid 90s, and gradually returning
moisture keeping the radar scope active during the afternoon
hours.

Guidance begins to diverge this weekend with respect to surface
boundaries and mesoscale features. There is the potential for a
second front, but even without a surface boundary involved,
returning moisture should assure rain chances persist. Increased
precipitable water values will enhance rainfall efficiency, and
in areas that encounter multiple rounds of significant rainfall
during this period, flooding issues may arise. Cloud cover will
correspondingly increase into early next week, stunting daytime
temperatures even without the impacts of rain-cooled air. Highs
may stay below 90F, potentially as much as 10 degrees below
normal during what is climatologically the hottest time of the
year. The GFS MOS is carrying a high of only 83F at DFW on Sunday,
which would likely require a significant rainfall component. In
any event, this will be a welcome respite from the summer heat,
one that looks to continue beyond the current 7-day forecast.

25

&&

.AVIATION... /NEW/
/12Z TAFs/

VFR will prevail through the period with south winds 10 to 15 kt
and occasional gusts to 25 kt. A cold front will approach the area
on Wednesday afternoon with scattered storm chances increasing.
This is just beyond the valid TAF period but will need to be added
with later issuances.

Dunn

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth   102  81  99  76  92 /   0   0  40  30  40
Waco                99  77  99  76  93 /   0   0  20  10  40
Paris              100  77  95  73  88 /   0   5  40  50  50
Denton             102  80  98  73  92 /   0   5  30  30  40
McKinney           102  80  99  74  91 /   0   0  40  40  40
Dallas             102  82 100  76  94 /   0   0  40  30  40
Terrell             98  77  97  73  90 /   0   0  40  30  50
Corsicana           98  77  98  76  92 /   0   0  20  20  50
Temple              99  75  98  75  94 /   0   0  10   5  30
Mineral Wells      102  77  99  73  92 /   0   5  30  20  40

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for TXZ091>095-100>107-
116>123-131>135-145-146.

&&

$$