689
FXUS64 KFWD 181023
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
523 AM CDT Wed Sep 18 2024

...New Aviation, Short Term...

.SHORT TERM... /NEW/
Update:
No significant changes to the previous short-term forecast. An
area of scattered to broken stratus is moving northward through
Central Texas this morning, and this will yield a period of partly
to mostly cloudy conditions mainly south of a Killeen-Waco-
Palestine line for a few hours shortly after daybreak. These
clouds should mix out by mid morning as solar insolation ensues.

Bradshaw

Previous Discussion:
/Today and Tonight/

North Texas will remain in the grip of an upper level ridge
extending from northern Mexico into the Central Plains. Subsidence
associated with this feature will continue to produce clear skies
and temperatures that are noticeably above normal for the last
half of September. Highs will climb well into the 90s across the
entire area later today, while lows tonight will only manage to
reach the lower 70s. A southerly flow regime will pump renewed
moisture into the region, contributing to heat indices that will
push past the century mark in many locales later today.

Bradshaw

&&

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

VFR conditions are still expected at all TAF sites through 12z
Thursday. Areas of MVFR stratus are moving northward through
Central Texas prior to daybreak, but these conditions should be
limited to areas south through east of Waco. Expect these clouds
to erode by mid morning as surface heating and mixing commences.

Southeast winds at speeds of 8-12 knots will veer to a southerly
direction by 15z as surface troughing increases in the lee of the
Rockies.

Bradshaw

&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    95  77  98  77  99 /   0   0   0   0   0
Waco                96  74  99  74  98 /   0   0   0   0   0
Paris               91  70  94  72  96 /   0   0   0   0   0
Denton              96  74  98  74  99 /   0   0   0   0   0
McKinney            95  74  97  75  98 /   0   0   0   0   0
Dallas              96  76  98  77 100 /   0   0   0   0   0
Terrell             94  72  97  73  99 /   0   0   0   0   0
Corsicana           96  75  98  75  98 /   0   0   0   0   0
Temple              97  73  98  72  98 /   0   0   0   0   0
Mineral Wells       96  73  97  72  99 /   0   0   0   0   0

&&

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

$$