FXUS64 KFWD 192234

Area Forecast Discussion
National Weather Service Fort Worth TX
534 PM CDT Sun May 19 2019

I have went ahead and removed late afternoon-early evening slight
chances of storms across Central Texas. GOES visible satellite has
shown cumulus field struggling to get going along and south of our
stalled surface front.

A couple of factors are likely playing into this:

1. Subsidence behind yesterdays storms and disturbance.

2. LAPS and RAP soundings showing an EML(likely from the aforementioned
residual subsidence) strengthening between 700mb-800mb. Also,
southwest flow aloft is amplifying in advance of a the next upper
system dropping south across CA/NV.

and finally...

3. Dry-air entrainment -- (moisture is minuscule thin both above
and below the EML).

Otherwise, the front should lift back northward toward the Red
River Valley after midnight and through daybreak Monday in
response to increasing 925mb-850mb to between 20-30 knots,
especially west of I-35. As such, patchy fog/drizzle remains
possible across Central Texas overnight with the increasing low
level warm advection.



.SHORT TERM... /Issued 337 PM CDT Sun May 19 2019/

There will be a low risk for showers and an isolated thunderstorm
this afternoon mainly across the Brazos Valley. While the CU field
looks a little less than impressive. This may be in response to to
lingering subsidence. However...the instability---thanks to 90
degree temperatures and dewpoints in the low to mid 70s---remains
quite robust at this hour. There will still remain a risk for
convective initiation through the late afternoon to early evening
hours southeast of a Temple to Mexia to Palestine line. A strong
or severe storm capable of strong to possibly damaging winds will
remain possible if a storm can mature.

The aformentioned front should lift northward tonight in response
to a deepening surface low to the northwest. Moisture will slosh
northward with the aid of southerly winds. The subsequent
WAA/isentropic upglide could result in some sprinkles or light
rain showers, but widespread measurable rain appears unlikely.
There will be a risk for some patchy drizzle or perhaps light
fog...especially south of I-20. At this time, winds aloft (around
925mb) may be too strong to preclude a more appreciable fog
episode across the region. Should these winds aloft underachieve,
then increasing low level moisture coupled with recent rainfall
could set the stage for a hybrid advection/radiation fog scenario
across the area.



.LONG TERM... /Issued 337 PM CDT Sun May 19 2019/
/Monday through Sunday/

A low pressure system will gather strength across the western U.S.
on Monday, resulting in a warm, humid and breezy day. Increasing
southerly surface winds will lift the cold front north of the Red
River quickly Monday morning while southwesterly flow aloft draws
warm air off of the Mexican Plateau, reinforcing the cap.
Therefore, storms are not expected for most areas during the day
Monday, but a few brief storms may develop on the retreating
front across the northwest zones in the morning along with a few
warm air advection sprinkles farther south. Isolated to scattered
storms are possible across the northwest zones during the
afternoon/early evening on outflows from West Texas/Southwestern
Oklahoma storms, but the cap may hold until stronger forcing

Additional storms are expected to develop across the Low Rolling
Plains and Permian Basin Monday evening as the powerful upper low
pivots northeast towards the Central High Plains. The storms
should organize into a linear complex as large scale lift, mid
level instability and deep layer shear increase. The line of
storms will enter into western North Texas late in the evening and
spread eastward through the night/Tuesday morning. Damaging winds
will be the primary hazard, but some storms may contain hail. An
overall decrease in storm strength is anticipated as the line
moves east of the I-35 corridor from mid morning through early
afternoon Tuesday. However, storm intensification is likely during
the heat of the afternoon, but this should occur east of the
forecast area. We will have to watch the speed of the line closely
since a slower progression would result in a better chance for
strong to severe storms across the eastern zones Tuesday

We were considering a Flash Flood Watch for portion of the area
for Monday night/Tuesday since most areas received appreciable
rainfall yesterday. However, moisture should remain confined below
850 mb with this system and the progressive nature of the
anticipated line should keep rainfall totals generally less than
an inch. If future guidance suggests slightly deeper moisture or
slower speed of the storms, later shifts may need to issue a Flash
Flood Watch.

Rain/storm chances will end Tuesday night once the lead upper low
moves toward the Northern Plains and an amplified ridge begins to
nudge in from the east. Although the upper ridge axis should
remain east of the region, its presence should keep North and
Central Texas warm and generally rain free the second half of the
week through the weekend. It will remain humid, however, with low
pressure in the west keeping a constant influx of Gulf moisture.
It does look like storms will remain a possibility across West
Texas and western Oklahoma the second half of the week as a series
of weak disturbances move through southwest flow aloft. These
storms may send some outflows toward the northwest zones during
the afternoon and evening. Therefore, we will maintain some low
PoPs in that area generally Thursday through Saturday.

Temperatures next week will be near or above seasonal normals
with highs generally in the middle and upper 80s and lows ranging
from the middle 60s to the middle 70s.



.AVIATION... /Issued 116 PM CDT Sun May 19 2019/
/18 UTC TAF Cycle/

Concerns---Gradual wind shift and ceiling trends.

VFR currently prevails at all TAFs this afternoon in the wake of
a cold front. A few showers and perhaps a thunderstorm or two may
develop to the south and east of ACT where activity should remain
late this afternoon and into the evening. The cold front will
stall and lift northward---as a warm front---through the
overnight hours. East winds will accompany the warm frontal
passage along with the potential for MVFR and occasional IFR cigs
starting just after midnight and continuing through the Monday
morning push. There is a chance for BR or even FG...but breezy
winds should preclude this threat. Trends will need to be
monitored, however, as weaker low level winds could result in IFR
or LIFR vsby. Confidence in MVFR cigs occurring at at all
terminals is high...with medium confidence in IFR cigs. There does
appear to be weak ascent associated with the front, so I cannot
rule out a period or two of showers...but this potential looks
greatest to the west of I-35. Otherwise, increasing southerly flow
is anticipated from mid-morning Monday through Monday evening as
surface winds crank to near 20 knots.



Dallas-Ft. Worth 70 86 70 81 67 / 5 10 40 70 10
Waco 72 88 72 83 68 / 10 10 30 60 10
Paris 66 84 70 78 64 / 0 10 30 60 10
Denton 68 86 67 79 64 / 5 20 40 70 10
McKinney 67 85 69 79 64 / 5 20 30 70 10
Dallas 72 87 71 81 68 / 5 10 30 70 10
Terrell 70 87 71 79 66 / 5 10 30 60 10
Corsicana 73 88 71 80 69 / 10 10 30 60 10
Temple 73 88 72 82 68 / 10 10 30 60 10
Mineral Wells 67 86 65 81 62 / 10 20 60 50 5




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