422 
FXUS64 KFWD 121042
AFDFWD

Area Forecast Discussion
National Weather Service Fort Worth TX
542 AM CDT Tue Sep 12 2023

...New Aviation, Short Term... 

.SHORT TERM... /NEW/
Update:
Our surface cold front is draped roughly from Cisco to DFW to
Paris as of 530 AM and is making slow southward progress. Weak
ascent associated with frontogenesis and warm advection in the
925-850mb layer will continue to support scattered shower and very
isolated thunderstorm activity, especially near and north of this
boundary through the morning. With only about 100-200 J/kg of
MUCAPE remaining across the forecast area based on latest
objective analysis, the potential even for lightning is quite low,
but can't rule out a few rumbles of thunder the rest of this
morning. Most of this activity is expected to wane by midday, with
some dry time through much of the afternoon and evening. The next
round of potentially heavier rain is expected to arrive overnight
into Wednesday with the greatest PoPs along the forecast 850 mb 
front's position near or south of I-20.

-Stalley

Previous Discussion:
/Through Wednesday/

Occasional shower and thunderstorm activity remains possible 
through the midweek period, as a slow-moving cold front eventually
stalls through Central Texas. This front is gradually progressing
through North Texas early this morning and will make steady 
southward progress today. Temperatures behind the front will be 
several degrees cooler, aided by fairly widespread cloud cover 
through most of the daytime. Rain chances will linger through the 
morning as weak and broad ascent occurs in the vicinity of this 
boundary in the form of mid-level height falls and low-level warm 
advection. While some occasional lightning strikes and gusty winds
are possible, severe weather is quite unlikely, and isolated
showers will be the predominant display on the radar.

Following the steady decay of morning precipitation, most of the 
daytime will be dry (especially the afternoon period) for the vast
majorly of the forecast area as we await a second mid-level 
disturbance set to arrive this evening/tonight. Renewed ascent 
along the 850mb frontal zone should result in a broad swath of 
showers and embedded thunderstorms. It remains uncertain as to 
where this axis of rainfall will materialize, but latest 00z 
guidance suggests the most likely location will be near or south 
of the I-20 corridor. Areas removed from this precipitation axis 
may stay dry for most or all of the night, outside of perhaps some
high-based isolated showery activity farther to the north which 
may struggle to produce measurable precipitation. 

While global guidance suggests widespread rain could continue into
the day Wednesday, this is currently not supported by much high-
res short term guidance, and have reduced PoPs markedly for the
Wednesday daytime period. However, widespread cloud cover should 
still be present which will help to hold highs in the 80s or upper
70s area-wide. Additional rain chances will continue into the 
latter half of the week as covered in the long term.

-Stalley

&&

.LONG TERM... /Issued 231 AM CDT Tue Sep 12 2023/
/Wednesday Night Onward/

Split flow will have developed by the start of the period with 
the southern jet flowing from the Desert Southwest through the 
Southern Plains, and the northern stream focused along the 
U.S./Canada border. At the surface, our cold front will extend 
along the Southeast Texas/Louisiana coastal areas westward 
through South-Central Texas. After briefly stalling, a slow and 
steady southward push is expected to resume, which will keep 
North and Central Texas in the "cooler" airmass through the end of
the week. Temperatures will range from lows in the 60s to highs 
in the upper 70s to mid 80s Wednesday night through Saturday.

Rain chances will persist through at least Saturday as a pair of 
shortwaves embedded in the southern stream make a slow approach 
from the west. Isentropic ascent will ramp up Wednesday night-
Thursday as the first disturbance moves east through the Southern 
Plains. A band of elevated convection will likely set-up somewhere
across the region during the Wednesday night-Thursday time frame.
The location of the best rain chances is uncertain and may depend
on where the 850mb front resides. Will keep POPs fairly broad at 
this time, and narrow down where the best rain chances will be as 
we enter the window of CAM guidance.

A lull in precipitation chances may occur on Friday as the 
initial shortwave exits to the east. The second disturbance will 
phase with a northern stream shortwave trough late Friday, with 
both swinging southeast from the Plains to the Mississippi Valley 
Friday night through Saturday. Widespread lift ahead of the phased
impulses will generate one more round of showers and storms 
Friday night and Saturday as a second cold front surges south 
through the region. Precipitation should come to an end by Sunday 
as the trough heads east and the front pushes south.

Despite the passage of the second front, temperatures will 
actually increase during the first part of next week as a mid 
level ridge builds in from the west in the wake of the departing 
trough(s). Temperatures should end up being slightly above normal 
early next week, with lows in the 60s and highs in the upper 80s 
to lower 90s.

30

&&

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

A cold frontal passage is occurring at DFW area airports as of
1030z, and a north wind at 10 kts or less will prevail the rest of
the period. Fropa is expected at Waco in a few more hours, and a
light and variable wind will continue there prior to its arrival.  
Scattered showers will accompany this boundary and persist behind 
it through the rest of the morning before a window of dry time 
this afternoon and evening. While a couple of lightning strikes 
cannot be completely ruled out across across North Texas over the 
next few hours, this potential is too low to warrant a prolonged 
window of TS in the TAFs. There is a small chance for some post- 
frontal low cigs in the 2-4 kft range to develop later this 
morning, but guidance suggests the lowest cloud deck will remain 
northwest of the D10 TAF sites. Another round of showers and 
storms is expected overnight into Wednesday morning, although 
placement and coverage remain uncertain at this time.

-Stalley

&&


.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    85  70  83  70  80 /  40  50  60  60  80 
Waco                88  69  82  70  85 /  40  80  80  60  70 
Paris               82  67  79  65  75 /  40  30  30  40  60 
Denton              84  66  83  67  80 /  40  50  40  60  80 
McKinney            83  67  82  66  77 /  40  40  40  50  70 
Dallas              86  71  83  70  82 /  40  50  60  60  80 
Terrell             87  68  83  67  80 /  30  50  60  50  70 
Corsicana           90  71  82  70  84 /  30  80  70  50  70 
Temple              92  70  86  69  90 /  30  70  70  50  60 
Mineral Wells       83  66  81  66  81 /  40  70  60  70  80 

&&

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

$$