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FXUS64 KFWD 032007
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
307 PM CDT Tue Jul 3 2018


.SHORT TERM...
/Through Tonight/

Rich tropical moisture, associated with an approaching easterly
wave, has begun spilling into East Texas. Precipitable water 
values are nearing 2.5 inches downstream of the trough's axis. 
Aided by daytime heating, showers and thunderstorms have developed
from the Gulf Coast to the Ozarks. The western edge of the CU
field has entered our CWA, but the subsidence further west has
maintained a persistence forecast today for North and Central
Texas. Convection may begin spilling into our eastern zones before
nightfall, but with the loss of daytime heating, the showers and
storms will spend the night closer to their trough axis home. Mid
and high clouds will increase from east to west overnight, but
this should have minimal impact on temperatures. Light surface 
winds will steadily back as the trough approaches.

25

&&

.LONG TERM...
/Independence Day through next Tuesday/

The easterly wave we've been monitoring for the last few days will
have pushed into Texas Wednesday morning, with an associated area
of showers and storms likely ongoing along the I-45 corridor 
across the Upper Texas Coast. As easterly flow deepens around the 
northern periphery of this feature, moisture will steadily 
increase through the day across North and Central Texas, with the 
70 degree isodrosotherm likely pushing to just west of the I-35 
corridor even during peak mixing/heating. The resulting moisture 
profile will be impressive, with PWATs easily pushing above the 
90th percentile for this time of year. That said, the multi- 
model consensus indicates the vast majority of forcing for ascent 
associated with DCVA will remain just south of our Central Texas 
counties as the main mid-level circulation drifts southwestward 
along the coastline. While it certainly won't take much to spark 
some diurnally-driven convection in the moisture-rich environment,
we'll have to rely more on just modest warm advection or 
differential heating-induced convergence to invigorate parcels to
their LFCs on Wednesday afternoon. This should only be good 
enough to warrant low (less than 30%) precip chances up to the 
I-20/30 corridors. Prospects look a bit better the farther south
you go into Central Texas where PoPs quickly increase to 50-60%.

Skinny CAPE profiles won't facilitate much in the way of DCAPE, 
but LCLs up around 5-6 kft will support a gusty wind threat with 
any cells. Brief heavy rainfall will also accompany any 
convection, but 15-20 kts of flow in the cloud-bearing layer will 
push things along at a good clip. Finally, temperature trends will
be tricky tomorrow. Most of the region will warm into the 90s to 
near 100 degrees with the highest temperatures across our 
northwestern counties. Across our southeast, more prevalent cloud 
cover and rainfall should help hold temperatures in the 80s, but 
any extended breaks will mean these temperatures end up too cool. 
Some very isolated pockets of 105-107 degree heat indices will be 
possible out west, but coverage and duration will be too minimal 
to support any heat headlines. 

As this first waves tracks westward, it will drag the best 
precipitation chances with it Wednesday night/Thursday. Persistent
easterlies will keep moisture values elevated, however, enough 
for some diurnal pop-up convection across our eastern and southern
counties Thursday afternoon. Low-level moisture should mix out a
bit better, and resultant afternoon inverted-V profiles will
foster a continued gusty downburst wind threat, but organized
severe weather is not anticipated. Activity should diminish 
around sunset.

By Friday and into Saturday, east to northeast flow will continue
around the southeastern quadrant of the Four Corner's high, which
will keep at least a low-grade risk for showers and storms going
across our Central Texas counties. At the same time, a backdoor 
cold front is slated to ooze towards the Red River, and this 
feature may bring North Texas its best chances for showers and 
storms through the forecast period. Broad-brushed 40-50% PoPs look
reasonable for Saturday. Temperatures in the lower to middle 90s 
on Saturday won't be as supportive for strong wind gusts, but 
forecast profiles still look pretty deeply mixed (up to 750 mb), 
supporting a continued threat for gusty precip-loaded downdrafts 
Saturday afternoon. 

The aformentioned mid-level high may never really build back 
overhead next week, and this could leave at least parts of the 
region open to some diurnally-driven thunderstorm chances. We've
left storm chances out of the forecast for Tuesday given
uncertainties regarding the positioning of the main moisture axis,
at least for the time being.  

Carlaw

&&


.AVIATION... /Issued 1258 PM CDT Tue Jul 3 2018/
/18Z TAFs/

VFR. SE winds becoming E. Thunder potential mainly S and E.

Subsidence will prevail today in advance of an easterly wave, with
clear skies and generally light southeast winds. Winds will back
to the east/northeast in response to the approaching trough, and
clouds will increase Wednesday from the top down. The associated 
showers and isolated thunderstorms will mainly impact Central and 
East Texas. Waco would be the more likely TAF site to be impacted
by convection, but this would be beyond the current TAF period. It
appears the bulk of the activity will impact south departures and
southeast arrivals.

25

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    79  96  77  95  78 /   5  10   5  20  10 
Waco                78  94  74  97  75 /   5  40  20  20  10 
Paris               75  93  75  93  75 /  20  10   5  30  10 
Denton              77  95  75  95  76 /   5  10   5  10  10 
McKinney            77  93  75  93  76 /   5  10   5  20  10 
Dallas              81  96  78  97  79 /   5  20   5  20  10 
Terrell             77  93  75  96  76 /  10  20   5  30  10 
Corsicana           77  93  73  95  76 /  10  30  10  20  10 
Temple              77  92  72  94  74 /   5  50  30  20  10 
Mineral Wells       76  99  73  96  74 /   0  10   5  10  10 

&&

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

$$

90/25