Severe Thunderstorm Warning 66, NWS Tucson, AZ

891 
WWUS55 KTWC 222110
SVSTWC

Severe Weather Statement
National Weather Service Tucson AZ
210 PM MST Thu Aug 22 2019

AZC003-023-222120-
/O.EXP.KTWC.SV.W.0066.000000T0000Z-190822T2115Z/
Cochise-Santa Cruz-
210 PM MST Thu Aug 22 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN COCHISE AND
SOUTHEASTERN SANTA CRUZ COUNTIES WILL EXPIRE AT 215 PM MST...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty 
winds and heavy rain are still possible with this thunderstorm 
through 230 pm.

LAT...LON 3135 11064 3152 11046 3141 11027 3133 11032
      3133 11061
TIME...MOT...LOC 2110Z 033DEG 4KT 3138 11045 

$$

Cerniglia

Area Forecast Discussion
National Weather Service Tucson AZ
950 AM MST Thu Aug 22 2019

.SYNOPSIS...A more active monsoon pattern will occur through
this weekend with temperatures returning to near or slightly below
normal. High pressure returning for the first half of next week will
usher in drier conditions once again along with above average
temperatures.

&&

.DISCUSSION...Skies are clear for the time being across Southeast
Arizona as indicated by visible and IR satellite imagery. Surface
observations indicate moisture continues to return to the region
with dewpoints in the low and mid 60's in many valley locations. The
added moisture is keeping temperatures a few degrees cooler compared
to 24 hours ago, and our highs later this afternoon should follow
suit, even though values will still peak above normal. PWAT on the
22/12Z KTWC RAOB was just under 1 inch, but we have more instability
to work with today with MU-CAPE around 1200 J/kg and a LI of -3.
Many CAM solutions including the U of A WRFNAM, WRFGFS and 4km NAM
Nest were fairly consistent with hitting Cochise, Santa Cruz and
southern Pima Counties pretty hard this afternoon with convection
and heavy rainfall. Expect storms to initiate over terrain first
before moving into the valleys with colliding outflows and
subsequent storm development to be the story. With 1800 J/kg of
DCAPE from the sounding this morning, we expect the primary threat
today to be gusty winds with a few strong or even severe storms.
With how hot and dry its been the last several days, expect outflows
to kick up some dust across mainly Pima County as storms move
westward, with reduced visibility at times. All this said, made some
short term tweaks to the grids regarding PoPs and QPFs as well as
added blowing dust to the weather grids. For more information on the
forecast into this weekend and beyond, please refer to the previous
discussion.

&&

.AVIATION...Valid through 23/18Z.
FEW-SCT clouds at 10k-14k ft MSL west of KTUS and SCT-BKN clouds
south and east of KTUS through the forecast period. Isolated to
scattered TSRA/SHRA will develop early this afternoon primarily from
KTUS/KOLS eastward with brief MVFR vsby/cigs possible, particularly
near terrain. Precip decreasing this evening though a few -SHRA
could linger overnight near the International border including
KDUG/KOLS. Gusty outflow winds are possible near TSRA/SHRA up to
around 40 kts. Otherwise, SFC wind mainly SWLY to WLY around 7-14
kts becoming primarily SLY overnight. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...Mainly afternoon and evening thunderstorm chances
increase starting today to include much of southeast Arizona and
will continue into the weekend before drier weather returns early
next week. The return of deeper monsoonal moisture will allow
temperatures to fall back to near seasonal levels by Friday which
will remain through the weekend before warmer temperatures return
next week. Any thunderstorms that do develop may produce gusty and
erratic outflow winds. Otherwise, 20-ft winds will generally follow
normal diurnal trends at less than 15 mph.

&&

.PREV DISCUSSION...Latest models continued to advertise a more
activate thunderstorm pattern developing through this coming
weekend. Deep moisture pooled south of the region was progged to
spread northward into southeast Arizona by late Friday. This
increase in moisture will signal an upswing in daily showers and
thunderstorms, especially on Friday and Saturday. This more active
thunderstorm pattern will be brief, as models showed another dry
spell for early next week along with a return of very hot
temperatures. In the meantime, the increase in moisture and
subsequent thunderstorms will help cool daytime temperatures to near
or slightly below normal.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...None.

&&

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