Special Weather Statement, NWS Tucson, AZ

Area Forecast Discussion
National Weather Service Tucson AZ
300 PM MST Fri Aug 3 2018

.SYNOPSIS...Daily rounds of isolated to scattered thunderstorms
can be expected into next week. Some storms will generate heavy rain
and strong winds. Temperatures will remain several degrees above
average for early August.

&&

.DISCUSSION...Upper level ridge axis today extended from off the
southern California coast east into west Texas. Further northeast
there is an upper level trof moving through Colorado/nrn New
Mexico. Overall this has put southern Arizona under light W-NW flow
aloft. Thunderstorm activity this afternoon has been limited to
areas east and south of Tucson and mainly favoring the mountains.
Locally strong wind gusts and heavy rain possible with these
storms.

Both GFS/NAM have a thunderstorm complex later this evening over
northeast Sonora which could send outflows north into Cochise
county where elevated thunderstorms are possible during the
overnight hours.

Mid-level flow turns to the east on Saturday. The combination of
warm mid-level temperatures around -3C to -4C along with below
normal PW values for early August will result in only isolated
thunderstorms along the International border and up in the White
Mountains. Similar story on Sunday. Highs over the weekend will
run 4 to 6 degrees above normal.

Next will see an increase in thunderstorm activity under easterly
flow aloft. Picking a day which will be the first up day is a
little tricky right now. At this time looks like Tuesday will be
that day. Will keep an eye on the tropics as models move a
hurricane well west of the southern tip of Baja. May be close
enough to enhance moisture across northern Mexico. Stay tuned.

High temperatures early next week remaining 3 to 5 degrees above
normal then cool closer to normal to end the week under added
moisture and cloud cover.

&&

.AVIATION...Valid through 05/00Z.
Scattered -TSRA/-SHRA mainly east to south of KTUS into this evening,
decreasing in coverage after sunset. Cloud bases are generally
10k-15k ft AGL. Surface winds remain less than 12 kts following
typical diurnal flow, with the possibility for possible
thunderstorm induced gust to 40 kts. Aviation discussion not
updated for TAF amendments.

&&

.FIRE WEATHER...Scattered thunderstorms will favor locations mainly
east to south of Tucson into this weekend. Isolated to scattered
thunderstorms then prevail areawide Monday into next Friday. 20-foot
winds remain terrain driven at less than 15 mph, with slightly
gustier afternoon conditions across the Upper Gila River Valley over
the weekend. Daytime temperatures hit a few to several degrees above
normal through a majority of the forecast.

&&

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

&&

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Special Weather Statement
National Weather Service Tucson AZ
218 PM MST FRI AUG 3 2018

AZZ507-513-032200-
Upper San Pedro River Valley including Sierra
Vista/Benson-Dragoon/Mule/Huachuca and Santa Rita Mountains including
Bisbee/Canelo Hills/Madera Canyon-
218 PM MST FRI AUG 3 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN COCHISE COUNTY UNTIL
300 PM MST...

At 217 PM MST, Doppler radar was tracking a strong thunderstorm just
east of Sierra Vista, moving southeast at 10 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Sierra Vista, Bisbee, Sierra Vista Southeast, Palominas, Hereford and
Junction Of Highways 80 And 90.

LAT...LON 3151 11029 3164 11014 3148 10989 3133 11009
      3133 11017
TIME...MOT...LOC 2117Z 318DEG 9KT 3153 11018

EC

Special Weather Statement
National Weather Service Tucson AZ
303 PM MST FRI AUG 3 2018

AZZ507-508-512-513-032245-
Upper San Pedro River Valley including Sierra
Vista/Benson-Dragoon/Mule/Huachuca and Santa Rita Mountains including
Bisbee/Canelo Hills/Madera Canyon-Chiricahua Mountains including
Chiricahua National Monument-Eastern Cochise County Below 5000 Feet
including Douglas/Willcox-
303 PM MST FRI AUG 3 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL COCHISE COUNTY
UNTIL 345 PM MST...

At 302 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from 15 miles northwest of Douglas to near Bisbee.
Movement was east at 10 mph.

Wind gusts of 50 mph and blowing dust will be possible with these
storms.

Locations impacted include...
Douglas, Bisbee, Naco, Bisbee-Douglas Airport and Pirtleville.

LAT...LON 3136 10998 3158 10974 3152 10934 3133 10955
      3134 10994
TIME...MOT...LOC 2202Z 290DEG 10KT 3151 10973 3140 10985

EC

Special Weather Statement
National Weather Service Tucson AZ
635 PM MST FRI AUG 3 2018

AZZ507-508-513-040215-
Upper San Pedro River Valley including Sierra
Vista/Benson-Dragoon/Mule/Huachuca and Santa Rita Mountains including
Bisbee/Canelo Hills/Madera Canyon-Eastern Cochise County Below 5000
Feet including Douglas/Willcox-
635 PM MST FRI AUG 3 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN COCHISE COUNTY UNTIL
715 PM MST...

At 634 PM MST, Doppler radar was tracking a strong thunderstorm near
Sierra Vista Southeast, or 9 miles southeast of Sierra Vista, moving
southeast at 10 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Sierra Vista Southeast, Palominas and Hereford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall is also occurring with this storm, and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3152 11025 3154 11008 3133 10994 3133 11019
TIME...MOT...LOC 0134Z 334DEG 7KT 3147 11017

KD