-- Discussion containing changed information from previous version are highlighted. --
819
FXUS64 KFWD 181812
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
112 PM CDT Wed Sep 18 2024

...New Short Term, Aviation...

.SHORT TERM... 
-- Changed Discussion --
/NEW/
/Through Thursday Afternoon/

An upper level ridge will continue to strengthen through the end
of this week, leading to increasingly warmer temperatures each
afternoon. Highs will range in the mid to upper 90s for most of
North and Central Texas, with overnight lows in the low to mid
70s. Southerly winds around 5 to 10 mph with gusts upwards of 20
mph will be possible both this afternoon and tomorrow afternoon.
Otherwise, expect rain-free conditions and generally sunny skies
outside of some fair weather cumulus. There is a low chance for
some low lying stratus tomorrow morning across portions of Central
Texas, but this will generally remain impact-free for most.

Temperatures will continue to be on the rise on Thursday, which
is abnormal for this time of year. A few sites may even hit the
century mark out west tomorrow, so it will certainly not feel like
we are only days away from the autumnal equinox.

Reeves
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&&

.LONG TERM... /Issued 329 AM CDT Wed Sep 18 2024/
Update:
The current forecast generally remains on track with anomalous
heat persisting through the weekend amid the prevailing mid-level
ridge. Increasing mid-level heights and inflated temperature
anomalies in the 850-700 millibar layer signal particularly strong
heating beginning Thursday. Daytime temperatures have been
adjusted above NBM guidance in favor of recent trends in the MOS
guidance. Friday is currently forecast to be the warmest day of
the week with parts of North Texas topping out around 100F and
widespread triple digit heat indices. Precipitation prospects
unfortunately remain negligible for most areas until at least the
middle of next week. The previous forecast discussion is appended
below for reference.

12

Previous Discussion:
/Thursday Through Early Next Week/

Unseasonably strong ridging will intensify into the weekend above
the Southern Plains as persistent troughing dominates both the
West and the East. Temperatures will steadily climb in tandem with
rising 500mb heights, which will top 5900m by Friday. All
available perfect-prog guidance projects 500mb temperatures above
the Dallas/Fort Worth Metroplex will rise above -1C (into the 30s
in Fahrenheit) on Friday. The NAM has 500mb temperatures above
freezing! This isn`t just near-record for September but would
challenge the all-time record high 500mb temperature for our local
weather balloons (1950 to present), which is -0.5C from July 1951.
Despite intense subsidence and similarly impressive temperature
anomalies at 700 and 850mb, a remarkably humid boundary layer,
combined with the shorter days and lower sun angles of September,
may keep Friday`s high temperatures below daily record highs
(values in the climate section below). MOS guidance has highs near
100F Friday afternoon for many locations, including DFW and Waco.
Heat index values will exceed 100 across much of the region late
in the week and into the upcoming weekend, with the highest values
occurring on Friday.

An upper low will emerge from the Rockies on Saturday. Although
its associated cold front will likely get no closer than the Texas
Panhandle, it will reorient our upper ridge. Combined with an
influx of high clouds, this may shave a few degrees off afternoon
temperatures on Saturday. However, there will still be the
potential for temperatures to threaten the century mark in some
locations. Decaying frontal convection from West Texas may invade
from the west Saturday night into Sunday morning; these showers
are the only rain chances in the 7-day forecast.

Early next week, the ridge will be displaced to our south. While
this will bring an end to the threat of triple digits,
temperatures will remain above normal with highs generally in the
90s Sunday through Tuesday. However, extended guidance knows that
cold fronts cluster around the autumnal equinox (which is on
Sunday). Although there is considerable disparity among
operational solutions and ensemble members, there is some hope for
a cold front during the middle of next week. But don`t break out
the winter coats just yet; the Climate Prediction Center continues
to favor above normal temperatures through the end of the month.

.CLIMATE...

Record Highs for September 20 (Friday)
   DFW       102 in 1953
   Waco      101 in 2021
   Killeen   100 in 2021

(DFW Airport was 100 degrees on September 20, 2021.)

Although all 3 sites recorded later triple-digit days last year,
each location has only reached the century mark this late in the
year (September 20 and later) 5 years this century.

25

&&

.AVIATION... 
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/NEW/
/18z TAFs/

Concerns...Low Chance For MVFR Across Waco Tomorrow Morning.

VFR will generally prevail across all TAF sites through the
period. Southerly flow has more or less been reestablished across
the region, around 10 knots with occasionally higher gusts
possible through the afternoon. Otherwise, expect sunny skies with
passing fair weather cumulus. There is a low chance (<20%) of
MVFR to perhaps IFR ceilings across portions of Central Texas
tomorrow morning. This may briefly impact Waco through 13-16z.

Reeves
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&&


.PRELIMINARY POINT TEMPS/POPS...
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Dallas-Ft. Worth    77  98  77  99  77 /   0   0   0   0   0
Waco                74  98  74  98  73 /   0   0   0   0   0
Paris               70  95  72  96  72 /   0   0   0   0   0
Denton              74  98  74  99  74 /   0   0   0   0   0
McKinney            74  98  75  98  75 /   0   0   0   0   0
Dallas              76  99  77 100  77 /   0   0   0   0   0
Terrell             72  97  73  99  74 /   0   0   0   0   0
Corsicana           75  98  75  98  74 /   0   0   0   0   0
Temple              73  98  72  98  71 /   0   0   0   0   0
Mineral Wells       73  98  72  99  73 /   0   0   0   0   0
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&&

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

$$