Wildfire in Texas, August 20 to 23, 2020

Area Forecast Discussion
National Weather Service Amarillo TX
1244 AM CDT Thu Aug 20 2020

.AVIATION...
06Z TAF Issuance...VFR conditions are expected at DHT through the
period, but AMA/GUY may see MVFR conditions due to some isolated
thunderstorms over the next few hours. VCTS has been mentioned for
both sides with storms popping up around the area. There is a
slight chance a storm or two could pass over either TAF site,
but at this time confidence was only high enough to include VCTS.
Winds may become gusty and variable with these storms, but for the
most part winds are expected to be out of the south southeast at
5 to 15 knots with gusts up to 20 to 25 knots possible.

Rutt

&&

PREV DISCUSSION... /Issued 216 PM CDT Wed Aug 19 2020/

SHORT TERM...Today through Tomorrow Night...

Synopsis: Upper level high pressure continues to dominate over
the Desert Southwest as cyclonic flow persists over most of the
Eastern CONUS. North to northwest flow will be common over the
central and southern plains through the short term. The flow
fields from 500mb to 250mb are modest, with a jet streak helping
boost winds to around 35 to 40 knots. Some upper level divergence
has promoted a deck of altocumulus with showers and occasional
lightning over the eastern third of the combined Panhandles. This
has helped keep temperatures well below the blended solution, with
80s in the east and low to mid 90s in the west where clouds are
much less. Surface dew points were generally in the mid 50s across
the east, with upper 40s in the far west. Some mountain
convection was forming over the Sangre De Cristos, with additional
development possible further east by late this afternoon as a
subtle shortwave moves out of CO. A similar scenario should play
out tomorrow.

Mesoscale Details: For storm development later this afternoon,
the big questions will be if the cap can be overcome. This seems
highly unlikely in the eastern half of the Panhandles given lower
temperatures and cloud cover. However, for the western third or at
least the far west, convective temperatures should be reached.
There is a dry layer of air around 850mb that could limit storm
updrafts, along with lower instability (MLCAPE around 600 to 1000
J/kg). However, vertical shear is present today with effective
shear around 40 to 50 knots. Hodographs enlarge this evening as a
low level jet strengthens. Current thinking is that updrafts may
struggle to fully realize what shear is available given the weak
fairly skinny CAPE (inverted-V profiles). However, can't
completely rule out a mesocyclone if an updraft happens to
overachieve (which does happen in the Panhandles). With high LCLs
and DCAPE around 1000 to 1500 J/kg, wind will be the primary
severe threat. If mesocyclogenesis occurs, severe hail can't be
ruled out. The severe threat should generally decrease through the
evening, however a few elevated showers and storms could linger
or even re-form with support from the low level jet well after
dark in the central and eastern Panhandles.

For tomorrow, flow aloft picks up a bit more of a westerly
component. Thus, showers and storms have a better chance to move
off the higher terrain and into our western zones. Will also have
to see if there are any left over outflow boundaries in the area
from today's convection which could be a source for development.
Severe parameters are similar to today. Temperatures should be in
the 90s for most of the area.

Ward

LONG TERM (Friday through Tuesday)...

Main thing for the long term is the thunderstorm potential
Friday, albeit low chances mainly in the evening/overnight hours.
Otherwise, we will have to watch how the persistent upper level
high over the Desert Southwest positions itself beyond Friday
because the rest of the forecast is dry with current model
analysis.

Looking into Friday specifically, we have the H5 high centered
over Arizona, and this puts us in a northerly flow regime. This
pattern is a little concerning for our precipitation chances, and
current thinking is we may not see much at all. Our main chance
would be from convection that forms either off the higher terrain
(NM/CO) or somewhere in western Kansas, and somehow gets steered
into the Panhandles. However, these chances are not looking good.
Not going to completely rule it out at this point, but did trend
towards a slightly drier solution than what the blend of models
output. This resulted in carrying ~20% PoPs Friday/Friday evening.
That said, any storms that form could become severe with
effective shear around 35-50 knots within high based thunderstorms
potentially tapping into 500-1500 J/kg of instability. Inverted-v
soundings suggest damaging wind gusts from downbursts as well.

Beyond Friday, trend continues to show conditions favorable for a
dry forecast. Temperatures will be above normal, especially this
weekend where some areas will be around 100-103. The Canyon
especially will be close to heat advisory conditions, so canyon
goers should be prepared for hot conditions at Palo Duro Canyon
over the weekend.

Guerrero

&&

.AMA Watches/Warnings/Advisories...
TX...None.
OK...None.

&&

23/15

Hazardous Weather Outlook
National Weather Service Amarillo TX
221 PM CDT Wed Aug 19 2020

OKZ001>003-TXZ001>020-317-200730-
Cimarron-Texas-Beaver-Dallam-Sherman-Hansford-Ochiltree-Lipscomb-
Hartley-Moore-Hutchinson-Roberts-Hemphill-Oldham-Potter-Carson-
Gray-Wheeler-Deaf Smith-Randall-Armstrong-Donley-Collingsworth-
Palo Duro Canyon-
221 PM CDT Wed Aug 19 2020

This Hazardous Weather Outlook is for the Texas and Oklahoma
Panhandles.

.DAY ONE...This Afternoon and Tonight.

Isolated thunderstorms will be possible across much of the
Panhandles through tonight. A few storms may become severe with
damaging winds the main threat across the western Panhandles.
Hail will also be possible.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Isolated to scattered thunderstorms will be possible across much
of the Panhandles Thursday and Friday. A few storms may become
severe with damaging winds the main threat. Hail will also be
possible.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated at this time.