596
FXUS64 KFWD 171043
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
543 AM CDT Tue Sep 17 2024

...New Short Term, Aviation...

.SHORT TERM... /NEW/
/Today and Tonight/

No major changes to the previous short-term forecast. An expansive
deck of low cloudiness covers the areas northeast through east of
the Metroplex, and continues to edge slowly westward. This
cloudiness is borne on a modest fetch of easterly winds emanating
from northwest Louisiana. These clouds may have enough momentum to
blanket the eastern portion of the Metroplex for a few hours this
morning, but daytime insolation should erode them by early
afternoon.

Otherwise, mostly sunny and warm conditions will prevail areawide.
Our trend of above normal daytime temperatures for mid September
continues.

Bradshaw

&&

.LONG TERM... /Issued 255 AM CDT Tue Sep 17 2024/
/Wednesday and beyond/

As a persistent ridge of high pressure maintains unseasonably
warm temperatures across the Southern Plains on Wednesday, a
strong mid-level low/shortwave trough will lift across the
northern Rockies and northern Plains. Though the southern Plains
mid-level ridge will remain tethered to the state through the
forecast period, the expanding western U.S. trough will tilt the
ridge axis across North and Central Texas. The eastward shift of
the associated low level thermal ridge will inflate 850 mb
temperatures locally by an average of 4 to 7C according to model
projections. This is good for about the 90th percentile of the
historical temperature distribution in both the NAEFS and ECMWF
ensembles. Mixing to the surface during peak daytime heating,
this will translate to widespread highs in the mid to upper 90s
each afternoon. For this time of year, the average high at DFW and
Waco is 87F and 90F, respectively. Adjustments have been made to
account for the deep vertical mixing expected which should allow
dewpoints to mix out on these hot and dry afternoons, up to
several degrees below the current NBM guidance. The resulting heat
indices should peak below Heat Advisory criteria, however heat
safety precautions should still be considered if spending time
outdoors this week.

As the first shortwave ejects into the Canadian Prairies, another
upper level low pressure system will dive down the West Coast
reaching central California by Thursday morning. This feature is
progged to track across the Rockies and move into the Plains this
weekend. Unfortunately, any previously held hopes of returning
(low) rain chances and seasonally appropriate temperatures late
this weekend and into the following week have vanished as the
shortwave and associated frontal boundary look to remain on a
track north of the forecast area. This will keep the subtropical
ridge in control of our sensible weather through the end of the
period. Favoring a status quo forecast for day 6 (Sunday) and
beyond, temperatures have been raised above the MOS and NBM
guidance to near the NBM 50th percentile. As always, forecast
details for this time period will continue to change/update as we
go through the rest of the week.

12

&&

.AVIATION... /NEW/
/12z TAFs/

An expansive deck of MVFR and IFR stratus continues to spread
slowly westward across portions of North Texas this morning.
Believe at least KDAL may see a brief period of BKN IFR
conditions, and possibly even KDFW as well. Am doubtful that any
other TAF sites will be impacted, as the momentum of this
cloudiness should decrease by sunrise. Ample sunshine should lead
to an erosion of this cloudcover from mid morning onward, leading
to VFR conditions by 17-18z. Light east southeast winds areawide
will back to a small degree after 18z, leading to east or east-
northeast conditions at the Metroplex TAF sites during the
afternoon.

Bradshaw

&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    91  74  95  76  96 /   0   0   0   0   0
Waco                94  72  96  74  96 /   0   0   0   0   0
Paris               85  69  91  71  95 /   0   0   0   0   0
Denton              92  71  96  75  98 /   0   0   0   0   0
McKinney            91  70  96  74  98 /   0   0   0   0   0
Dallas              93  73  96  76  98 /   0   0   0   0   0
Terrell             90  69  95  73  96 /   0   0   0   0   0
Corsicana           93  73  96  74  98 /   0   0   0   0   0
Temple              95  72  97  73  97 /   0   0   0   0   0
Mineral Wells       93  70  96  73  98 /   0   0   0   0   0

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$