123 
FXUS64 KFWD 041054 AAA
AFDFWD

Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
554 AM CDT Sun Apr 4 2021

...New Short Term, Aviation... 

.SHORT TERM... /NEW/
Update:

No significant changes needed to the ongoing forecast. We will 
monitor the potential for some patchy shallow fog across the 
Brazos Valley this morning where a wedge of slightly drier air has
kept skies mostly clear. While dewpoint depressions are under 2-3
degrees, it's likely that fog development will be very shallow 
and does not appear to warrant inclusion in the worded forecast at
this time. Any fog will dissipate quickly after sunrise. I did 
nudge high temperatures up by a few degrees across the Brazos 
Valley, where a bit more sunshine will be possible. Still, high 
temperatures across the board should be in the upper 60s to mid 
70s. The risk for a few showers and isolated storms remains low 
and PoPs are capped at 20% for this update. The coverage of 
rain/storms should be such that a complete washout is unlikely for
those with outdoor festivities. 

Bain

Previous Discussion:
/Today through Monday/

Outside of low shower/isolated thunderstorm chances, the short 
term period will be largely uneventful. Even with a low rain/storm
potential, I don't anticipate that any Easter festivities will be
completely washed out. It will remain cloudy for most locales 
with mild conditions.

Surface analysis this morning revealed that low level moisture 
was continuing its' northward trek with clouds between 3,000-5,000
feet now blanketing a good portion of North and Central Texas. 
These clouds along with elevated breezes will keep temperatures in
the 50s for the most part around sunrise this Easter morning. An 
upper shortwave trough will emerge from the Permian Basin into the
Concho Valley over the next several hours. Lift ahead of this 
feature will spread across Central Texas and we are already seeing
some signs of that on regional radar imagery. With RAP analysis 
indicating around 50-250 J/kg of MUCAPE, there will be a risk for 
isolated storms. Severe weather is not expected, but the strongest
storm cores may be capable of small hail. 

With a bulk of the strongest ascent expected to reside closer to 
the Hill Country, we'll keep PoPs in the 20-30% range, though it's
quite possible that all precipitation will remain south of our 
Central Texas counties. Farther north toward the I-20 corridor, 
lift will be close to nil and I'll only advertise a slight chance 
for sprinkles. If the corridor of lift shifts northward, then 
we'll need to make some spatial alterations to PoP/Wx grid this 
morning. Regardless, QPF across our area remains well below 1/4 of
an inch and I still do not anticipate it being a complete 
washout. Of course, with outdoor festivities, if you hear thunder 
or see lightning, be sure to get to shelter and use the 30/30 
lightning/thunder rule.

Clouds are expected to hang tough for most areas today and that 
will only allow temperatures to climb into the 70s. If cloud cover
thins, then upward adjustments to the temperatures will be 
needed. Conversely, if ceilings lower and/or precipitation is more
widespread, the current forecast is too warm. Rain/storm chances 
will diminish through the day and into the evening hours.

Tonight into Monday should feature virtually no threat for 
showers or storms. South to southwest winds will increase and with
at least partly sunny skies, highs should climb into the upper 
70s and low 80s. 

Bain

&&

.LONG TERM... /Issued 310 AM CDT Sun Apr 4 2021/
/Monday Evening and Beyond/

The next upper low will drop southeast through the Rockies Monday
night and Tuesday before turning east and traversing the Plains 
Tuesday night and Wednesday. Starting late Monday, lee-rockies 
pressure falls and the subsequent tightening of the local pressure
gradient will create an uptick in low level southerly flow. Low 
level moisture will likewise be on the increase, which may 
generate some warm advection sprinkles across the area by Tuesday 
morning. Will keep the forecast dry at this time with generally 
overcast and breezy conditions as we get into Tuesday. 

As the upper low and its attendant surface cyclone sweep through 
the Plains, a Pacific cold front will surge southeast into the 
area Tuesday night into Wednesday. Veering flow aloft out ahead of
the front will shunt the majority of available moisture off to 
our east. This will keep rain chances limited to areas east of 
I-35, and these rain chances will likely be capped at around 30 
percent. For the rest of the region, breezy and warm conditions 
can be expected as the post-frontal airmass will contain mainly 
drier air as opposed to cooler air. In fact, though a strong storm
or two may affect the far eastern zones, the primary concern will
likely be an elevated threat of grass fires for areas along and 
west of Highway 281. Minimum RH values in the teens coupled with 
warm and breezy conditions will create this threat, but the hope 
is that significant green-up of vegetation will be a mitigating 
factor with regards to the spread of grass fires.

The front will begin to stall somewhere across Central Texas as 
the upper low heads for the Great Lakes and an upstream shortwave 
quickly approaches in the westerlies. This will likely keep 
temperatures above-normal on Thursday and Friday across the 
Central Texas counties while the rest of the region experiences 
near-normal temperatures. There is quite a bit of uncertainty 
regarding exactly where the boundary will lie, as well as the 
strength of the shortwave. The ECMWF and Canadian models have been
fairly aggressive with the intensity of the disturbance and 
subsequent convective development, so rain chances would then 
depend on the placement of the front. For this reason, have added 
a slight chance of thunderstorms for some of the region for 
Friday, and will refine the forecast later this week as more data 
becomes available. 

At this time it appears that shortwave ridging will provide dry 
and seasonable weather for next weekend, followed by additional 
rain chances as the next system approaches early next week.

30

&&

.AVIATION... /NEW/
/12 UTC TAF Cycle/

Concerns---None major. VFR with low convective potential at Waco.

VFR cigs around FL050 are expected through the entire TAF cycle 
with south winds near 10-12 knots. Brief gusts to near 15 knots 
cannot be ruled out. The threat of MVFR appears to have abated as 
most cigs that are below FL030 remain well west of the TAF sites. 
As mentioned previously, if low level flow turns more 
southwesterly and more widespread MVFR cigs develop across the 
Hill Country, cigs below FL030 may be need to be advertised in the
terminal forecasts. Otherwise, SHRA and embedded TSRA are still 
most probable south of Waco and the 12 UTC TAFs remain 
precipitation free.

Bain


&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    73  59  79  62  82 /  10   0   0   0   5 
Waco                72  56  79  61  83 /  20   0   0   0   0 
Paris               69  54  76  58  78 /  10   0   0   0   5 
Denton              73  58  79  59  81 /  10   0   0   0   5 
McKinney            72  57  78  60  80 /  10   0   0   0   5 
Dallas              73  59  80  63  83 /  10   0   0   0   5 
Terrell             73  55  78  60  80 /  10   0   0   0   5 
Corsicana           76  56  79  61  82 /  10   0   0   0   5 
Temple              75  55  79  60  83 /  20   0   0   0   0 
Mineral Wells       73  57  80  59  85 /  10   0   0   0   5 

&&

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

$$