Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

FXUS64 KFWD 201153

Area Forecast Discussion
National Weather Service Fort Worth TX
553 AM CST Wed Nov 20 2019

/12Z TAFs/

Low level clouds have invaded all of the North and Central Texas
TAF locations. With MVFR across the Dallas/Fort Worth Metroplex
and IFR at Waco, these conditions are expected to persist through
the early-afternoon. Daytime mixing will lead to VFR by mid-
afternoon and persist through around midnight. The low- level jet 
will be in full force for much of the day with winds in excess of 
40 kts at around 3000 feet AGL. With daytime heating, downward 
momentum transfer due to atmospheric mixing will lead to a breezy 
afternoon with sustained winds of around 20 kts and gusts up to 30
kts. These windy conditions are likely to subside after sunset as
the near-surface atmosphere decouples from the stronger winds 

Another slug of low level moisture will stream northward in 
conjunction with the strong low level jet. MVFR looks likely once 
again after midnight and into early Thursday morning.

Regarding the potential for rain, there are still some
uncertainties as to just how much rain coverage will occur this
afternoon. Most of the high resolution weather models keep the
bulk of the precipitation to the northwest, across the Bowie
cornerpost. There may still be some isolated to scattered rain
showers across the TAF sites, but given location and coverage 
uncertainty, will keep the afternoon mention of precipitation as 



.SHORT TERM... /Issued 320 AM CST Wed Nov 20 2019/
/Today and Tonight/

The main story today and tonight will be the increasing winds
throughout the day, followed by increasing rain chances this
afternoon and continuing through the night.

All these weather changes can be attributed to an upper level
trough that is now emerging out of the Mexican high terrain, and
is expected to move across the Four Corners region later this
afternoon. Given its distance from North and Central Texas, most
residents are expected to remain precipitation free. The 
exception will be in the northwestern counties, where lift is 
expected to be slightly higher due to the proximity to the passing

Increasing low-level cyclogenesis on the lee side of the Rockies 
will lead to an increasing response in the low level wind field 
throughout the day. Wind speeds at about 2000-3000 feet above 
ground level may increase to around 50 mph this afternoon. This 
will lead to some downward moment transfer as afternoon mixing 
takes place. Surface winds are expected to increase to around
15-20 mph this afternoon, with occasional wind gusts at around 
25-30 mph. 

Thunderstorm activity will remain heavily concentrated mostly to
the northwest of our area, but as the shortwave makes its closest
approach, a cluster of thunderstorms could skirt the Red River
counties. For the rest of the region, plenty of moisture will make
its way northward, and with warm temperatures in place, a few
warm advection showers and storms will be possible. The severe
weather threat throughout the region will remain low today and
tonight given the lack of significant instability. This shortwave
will continue moving to the northeast, and temporarily reduce the
probability of rain the region before rain chances return during 
the day Thursday.



.LONG TERM... /Issued 320 AM CST Wed Nov 20 2019/
/Thursday through Tuesday/

Thursday will be another cloudy and warm day across North and
Central Texas as Gulf moisture is drawn northward into an
approaching low pressure system. Highs Thursday will be in the 
70s region wide. Although some warm air advection showers and 
isolated thunderstorms will be possible through the day, the best
chances will be across the northern zones where a cold front will
stall. The cold front will continue to be a focus for showers and
thunderstorms Thursday night as it sinks slowly southward through
North Texas. Large scale forcing for ascent will increase as 
short wave energy ejects around the base of a strong upper low 
centered over the Four Corners region. Although mid level lapse 
rates will be marginal, moderate to strong shear may support a few
zealous updrafts which could produce small to marginally severe 
hail and possible some gusty downburst winds. 

The Four Corners upper low will lift to the Central Plains on
Friday, sending the cold front southward through the region.
Showers and isolated thunderstorms will accompany the front, 
followed by increasing dry/cold air advection from the north. All 
precipitation should exit the region early Friday evening, with 
clearing skies and much colder temperatures (30s and lower 40s) by
sunrise Saturday.

Dry northwest flow aloft, abundant sun and decreasing cold air 
advection Saturday will allow temperatures to warm into the middle
50s and lower 60s. Temperatures Saturday night will be cold with 
lows ranging from the mid 30s to the lower 40s. Sunday will be 
warmer (close to seasonal normals) with highs in the middle and 
upper 60s. Wind speeds will also be light Sunday as surface high 
pressure translates towards the Lower Mississippi Valley region.

Low level warm/moist advection will increase Monday in response to
a deepening lee trough across the Central High Plains. As a
result, it will be warmer and more humid Monday with highs from 
the mid 60s to the lower 70s. 

Shower and thunderstorm chances will return to the region Monday
night and Tuesday due to the approach and passage of an upper
trough and associated cold front. There are significant model
differences with regards to the strength of this system, so we
will keep PoPs low for now.



Dallas-Ft. Worth    76  65  74  50  57 /  10  40  60  70  60 
Waco                78  65  75  56  65 /  10  30  50  60  70 
Paris               74  61  72  51  57 /   5  60  70  70  70 
Denton              76  64  73  47  55 /  20  50  70  70  60 
McKinney            75  65  74  49  57 /  10  40  70  70  60 
Dallas              77  66  75  51  59 /  10  40  60  70  70 
Terrell             76  65  75  52  62 /   5  40  50  70  70 
Corsicana           77  65  74  56  64 /   5  30  50  60  70 
Temple              79  65  76  57  66 /  10  20  40  40  70 
Mineral Wells       77  62  72  46  54 /  40  40  50  70  50 



National Weather Service Glossary of Abbreviations