331 
FXUS64 KFWD 150946
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
346 AM CST Thu Feb 15 2018


.SHORT TERM...
/Today and Tonight/

Breezy and well above normal warmth is anticipated today. 
Measurable rainfall doesn't appear likely, though areas across 
East and Central Texas will have the opportunity for some patchy 
drizzle or a few sprinkles. The better rain chances, albeit still 
low, will come during the pre-dawn hours for areas near and east 
of I-35 and north of I-20. Much cooler conditions are also 
anticipated on Friday in the wake of the front and that will be 
detailed in the Long Term portion of the AFD.

Satellite imagery at this hour indicates that a plume of low 
level stratus continues to surge northward. This moist plume has 
been aided by a 50 knot low level jet per VWP. The increase in low
level moisture and wind speeds has allowed temperatures to remain
in the 60s across most of the area. The increase in winds should 
largely mitigate any significant reductions in visibility and I've
opted for patchy drizzle in lieu of fog for this morning. Some 
visibility may fall into the 3 to 5 SM range, but I don't 
anticipate a repeat of Wednesday morning with Dense Fog that 
occurred mostly across the Brazos River Valley and parts of East 
Texas. I'll also add in a mention of sprinkles through the morning
hours mainly near and east of I-35 as there remains some weak 
ascent. Measurable rainfall appears unlikely. Breezy south to 
southwest winds of 15 to 20 MPH with gusts to near 25 MPH will 
continue through the day and clouds will erode from west to east 
as southwesterly winds occur. With a southwest wind, temperatures 
will climb above normal values---especially where partly sunny 
skies are observed. Skies shouldn't be completely clear as a veil 
of mid/high level clouds will linger even after stratus 
dissipates. Highs today should climb into the mid to upper 80s out
across the Big Country with 80s closer to the I-35 corridor. 
Locales east of I-35 will likely remain mostly cloudy and 
temperatures will be held in the low to mid 70s. Similar to 
yesterday, if clearing occurs more readily/farther east, these 
forecast high temperatures (across East Texas) may be too low. 

For tonight breezy conditions will persist, though the magnitude 
of the wind speeds will decrease as the surface trough approaches 
and loosens the pressure gradient. Moisture should still have the 
ability to lift northward into the area and by midnight a cold 
front, currently across northern Kansas, should enter some of our 
counties along the Red River. Ongoing convection across Oklahoma 
should slip southward ahead of this boundary into the 
aformentioned counties, especially east of I-35. While activity 
will be convective in nature, MUCAPE values are quite low and 
under 100 J/kg. With that in mind, I'll keep the slight chances 
for showers in the forecast. By sunrise Friday, it appears 
probable that the front will be near the I-20 corridor. I've kept 
Friday MinT temperatures close to the previous forecast north of 
the boundary with lows occurring right a sunrise. South of the 
front, low level moisture and a 10 to 15 MPH wind should result in
another mild night across Central and parts of East TX.


24-Bain

&&

.LONG TERM...

/Friday through Wednesday/

A fairly strong cold front will be moving through North Texas by
Friday morning after a very warm day Thursday. Temperatures will
drop into the 40s behind the front and likely linger there all
afternoon. There is a low chance for some showers on the leading
edge of the boundary as it heads south, but most areas will remain
precipitation free through the day.

As we get into Friday night and early Saturday morning, a strong
shortwave trough will swing through the Central Plains resulting 
in an increase in warm moist southerly flow atop the colder air. 
Strong forcing between 850-700mb, where most of the moisture is 
located, will result in rapid development of showers during the 
late overnight hours Friday into Saturday morning. Rain should 
start out across the northwest counties and spread across the 
region though the first half of Saturday. This will be a fast 
moving wave of moisture, so while most areas will pick up some 
rainfall, amounts will generally be 1/2" or less. Temperatures 
will rebound some on Saturday as the colder air is eroded, 
especially out west where rain ends first.

Sunday's forecast is a little tricky as the guidance starts to
spread with respect to the handling of the upstream trough over
the western U.S. The GFS is a little less amplified and slower 
initially compared to the ECMWF. This results in slower lee side 
troughing and keeps North Texas in a cooler, weaker southeast flow
near the surface on Sunday. The ECMWF quickly returns strong 
southerly flow to the region, sending a plume of warm air across 
North Texas, effectively capping the region and allowing 
temperatures to warm into the mid 70s. While the front that 
settles into the region over the weekend isn't terribly cold, 
persistent cloud cover and rain through Saturday may keep things 
cooler into Sunday than currently forecast by the ECMWF. We'll 
side with cooler GFS during this time which means that we'll keep 
temps in the 60s and hang on to some PoPs areawide as moisture 
will again surge northward late in the day. This strong warm 
advection will likely result in at least some scattered showers.

There is some consensus with the overall trough amplifying through
the early part of next week. This will send a cold front through
the Plains on Monday. By Monday afternoon, we should become quite
warm again with a dryline approaching our western counties and the
front still well to the north. Latest guidance suggests that we 
will become unstable during the afternoon hours with around 
1000 J/kg of surface based CAPE and a decent deep layer shear
profile. There will be a lack of stronger forcing for ascent 
outside of low level warm advection, but we'll maintain some 30% 
PoPs through the afternoon. There may be some initial early day 
elevated showers that can become surface based during peak heating
given the generally weak capping. If this occurs, then a strong to
severe storm can't be ruled out.

The cold front will race into North Texas on Tuesday with a
continued chance for scattered showers and thunderstorms. Rain
chances appear to continue through the end of the week as the
upper pattern remains active across the western and central U.S.

Dunn

&&


.AVIATION... /Issued 1130 PM CST Wed Feb 14 2018/
/06Z TAFs/

Borderline IFR/MVFR ceilings tonight. VFR by Thursday afternoon.

In a 50-kt low-level jet, a finger of IFR ceilings made an early 
charge up the I-35 and I-45 corridors during the evening. The
westerly component within the cloud-bearing layer has made it
difficult for these ceilings to reach the Fort Worth airports. The
expanding blanket along the Balcones Escarpment will advect
northeast, assuring ceilings at all TAF sites by 09Z (3am CST).

Despite the stronger winds tonight, the early arrival of the cloud
deck and the additional moist advection that will occur during the
early morning hours will allow some reductions in visibility
within Central Texas. This is less likely to occur within the
Metroplex. 

Despite southwesterly winds on Thursday, considerable moisture
upstream will delay the erosion of the cloud deck. All TAF sites
should be VFR during the afternoon, but VFR ceilings may linger,
particularly at Waco. Another round of stratus is expected
Thursday night before a cold front arrives Friday morning; the
MVFR ceilings and FROPA wind shift have been introduced into the
extended portion of the DFW TAF with the 06Z package.

25

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    81  49  50  39  56 /  10  20  20  80  90 
Waco                76  54  57  39  53 /  10  10  10  60  80 
Paris               73  49  49  41  51 /  10  30  30  80 100 
Denton              81  47  48  38  56 /  10  10  20  80  90 
McKinney            77  48  49  38  54 /  10  20  20  80 100 
Dallas              79  51  51  41  55 /  10  20  20  80  90 
Terrell             74  52  52  44  53 /  10  20  20  80 100 
Corsicana           75  55  55  43  52 /  10  20  20  70  90 
Temple              74  60  61  41  53 /  10  10  10  60  70 
Mineral Wells       84  48  48  38  59 /   5  10  10  80  80 

&&

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

$$

24/91