Special Weather Statement, NWS San Angelo, TX

Area Forecast Discussion
National Weather Service San Angelo TX
244 PM CDT Sun Aug 6 2017

.SHORT TERM...
(Tonight)

...Heavy rain and severe thunderstorms possible...

Last nights convection/MCS over Oklahoma has produced an outflow
boundary that is moving southward across the southern panhandle.
This boundary, coupled with a slow moving east-west oriented cold
front will bring widespread showers and thunderstorms across the
area this afternoon and into the evening, with some storms becoming
severe. Storm Prediction Center (SPC) has much most of the area in a
marginal risk for severe thunderstorms. With temperatures climbing
into the upper 90s and dewpoint values greater than 64 degrees under
southwesterly flow. CAPE values have climbed in the 3000-3500J/kg
range. Upper level support is rather weak, but with the added lift
from the approaching cold front and the inverted surface trough,
expect rapid thunderstorm development with strong updrafts. The main
hazards with these storms will be the potential for strong downburst
winds in excess of 55mph. Heavy rainfall will also be possible with
these storms as PWAT values have climbed above 1.85". Both the HRRR
and the TTU-WRF model show large clusters of showers and
thunderstorms moving ESE across the Concho Valley and big County
through the evening. This will be the start of the heavy rainfall
event. Localized minor flash flooding is possible especially in poor
drainage and low lying areas. Rainfall totals through the evening
will be between a half to three quarters of an inch with localized
heavier amounts of up to one inch.

(Monday)

Showers and thunderstorms look to be fairly widespread across West
Central Texas, especially during the afternoon. Appears best push on
the front may be east of the area late tonight where a MCS may be
rolling across Central and East Texas. This would allow the front to
hang up across West Central Texas, combining with a little afternoon
heating and abundant moisture. After perhaps a lull in the
thunderstorm chances for the morning, showers and storms should
bubble up through the afternoon and become more widespread,
especially along and south of I-20. Will keep the PoP chances for
Monday at likely for most locations, and with precipitable water
values up over 2 inches for most areas and storm movement expected
to be slow, will continue the mention of locally heavy rainfall. Not
everyone will see big rain totals, but some areas will likely see 1
to 2 inches pretty easily.

As for temperatures, what may end up as a mostly dry morning will
allow readings to climb, with afternoon highs in the 80s to near 90
still looking reasonable.

.LONG TERM...
(Monday night through Saturday)

A weak cold front will remain stalled somewhere across the central
or southern portions of West Central Texas late Monday into Tuesday
night. This will remain a focus for shower and thunderstorm
development, so high end chance to likely PoPs were continued for
this period. Precipitable water values will generally be in the 2-
2.25 range, with some higher values. This abundant moisture will
result in the possibility of locally heavy rainfall. In addition, a
few strong storms will be possible, with strong gusty winds being
the main concern. High temperatures on Tuesday will be below
seasonal normals, in the mid to upper 80s.

The remnant weak cold front will still be in the vicinity of West
Central Texas on Wednesday, so isolated to scattered showers and
thunderstorms will once again be possible. Highs on Wednesday will
be slightly warmer, generally in the upper 80s to near 90 degrees.

Thursday into the weekend, weak upper level ridging will build
across West Central Texas. Disturbances are forecast to rotate
around the northern periphery of the ridge, resulting in shower and
thunderstorm development. At this point, it looks like the majority
of this convection will remain north and west of the forecast area,
but slight chance/low end chance PoPs were continued for mainly the
Big Country.

&&

.PRELIMINARY POINT TEMPS/POPS...
Abilene 	 73  86  70  86 /  70  70  60  50
San Angelo 	 74  90  71  88 /  60  60  60  60
Junction 	 73  92  72  88 /  30  60  60  60
Brownwood 	 73  89  71  87 /  70  70  60  70
Sweetwater 	 73  85  69  84 /  70  70  50  40
Ozona      	 72  90  71  87 /  30  40  60  60

&&

.SJT WATCHES/WARNINGS/ADVISORIES...
None.
&&

40/07/Daniels

Hazardous Weather Outlook
National Weather Service San Angelo TX
215 PM CDT Sun Aug 6 2017

TXZ049-054-064>066-071>073-076>078-098-099-113-114-127-128-139-
140-154-155-168>170-071915-
Fisher-Nolan-Sterling-Coke-Runnels-Irion-Tom Green-Concho-
Crockett-Schleicher-Sutton-Haskell-Throckmorton-Jones-Shackelford-
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Mason-
215 PM CDT Sun Aug 6 2017

This Hazardous Weather Outlook is for portions of west central
Texas.

.DAY ONE...This Afternoon and Tonight

Scattered thunderstorms are possible across West Central Texas
late this afternoon and tonight. A few of these storms may reach
severe levels, with damaging winds in excess of 60 mph the main
concern. In addition, as storms become more widespread late
tonight, some areas may see locally heavy rainfall and the
potential for flash flooding will increase. This would be
particularly true should the heavy rain occur over city streets,
urban areas, low water crossings, and other flood prone
locations.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

Storms should increase in coverage once again on Monday night and
continue into Tuesday. Again, the potential for heavy rainfall and
flash flooding looks to be the main threat, with some areas
perhaps seeing several inches of rain in a short amount of time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested at times this afternoon and
evening, and again on Monday.