567
FXUS65 KTWC 281712
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
1012 AM MST Fri Jun 28 2024

.SYNOPSIS...Southeast Arizona will continue to see enough
moisture for a daily chance of thunderstorms. Storm chances
increase over the weekend and early next week. Some storms will
generate strong winds and locally heavy rainfall.

&&

.UPDATE... Once again the favorable area for thunderstorm
development are areas south of Tucson today, mainly in southern
Cochise county and Santa Cruz county. Based on the latest 12Z
sounding, there is much more dry air aloft than the previous days,
allowing for some evaporative cooling as parcels begin to rise
and therefore increase the overall CAPE throughout the day. The
sounding also shows a PW of 1.51 inches, so the moisture is still
in place, even though it has been recycled over the past few
days. The sounding also has a bit of a cap, not as bad as
yesterdays, that will take some time to overcome before the storms
can tap into the CAPE. The RAP model has some areas of 1500-2000
J/kg in the areas of concern today, so there is some potential for
some stronger storms. The sounding also shows a bit of an
inverted V shape, hinting at some wet microburst potential for
some of the stronger storms, increasing the overall wind threat
for today. The DCAPE in the sounding is around 1400 J/kg and the
RAP keeps the higher values north and west of Tucson, but still
holds on to 1000 J/kg in its forecast for 23Z. The sounding also
shows storm relative motion to be relatively stationary, and thus
there is some flash flood potential for any efficient rain makers
or training thunderstorms over the same area. Much of southeast
Arizona is under some cloud cover this morning, limiting the
surface heating until this passes. CAMs continue to have storm
develop starting at 1pm over the higher terrain and continuing
into the evening.

So all in all, storm hazards for today are the strong to severe
wind from general thunderstorm outflows or microbursts, locally
heavy rainfall or training storms leading to flash flooding, and
potentially some small hail in the mix.

&&

.PREV DISCUSSION... /issued 300 AM MST Fri Jun 28 2024/

&&

.DISCUSSION...Last nights 500 mb upper air map placed the upper
high over northern Sonora with westerly flow over the area. PW
values were down a smidge but still running above late June norms.
For today, expect isolated to scattered showers/storms with the
best chances being focused across eastern Pima county, Santa Cruz
county and southern Cochise county. Brief heavy rain the main
concern today with PW values around 1.5", especially along/near
the Intnl border from Nogales east.

This weekend, as we close out an interesting June, an increasing
moist east-southeast flow aloft with high pressure to our east
will bring increasing chances of showers and thunderstorms, with
Sunday being the more active day.

Pattern next week leading up to the 4th of July holiday will keep
daily chances of showers and thunderstorms, with gusty winds and
heavy rain main threat from storms. However, there likely will be
one down day. Just can tell this far out which one.

Temperatures will remain on the warm side thru the next 7 days.

&&

.AVIATION...Valid through 29/12Z.
Decreasing debris clouds this morning. Widely scattered to
scattered -TSRA from 28/18z to 29/04z with brief MFR conditions
possible near storms. SFC winds generally 10 kts with the
occasional gust up to 20 kts this afternoon, except for gusty
outflow winds from storms. Aviation discussion not updated for TAF
amendments.

&&

.FIRE WEATHER...Relatively deep moisture will stick around through
the forecast period. This will bring widely scattered to scattered
thunderstorms and showers today and Saturday, mainly south and
east of Tucson. Moisture will increase more through the weekend
and into next week to bring higher chances and coverage for
thunderstorms and showers each day. Strong erratic gusty winds of
40 mph or higher can be expected with any storm development, along
with locally brief heavy rainfall. Outside of thunderstorm winds,
20-foot winds will generally be 15 mph or less each afternoon
with the occasional gust of 20 mph. Min RHs will generally be
around 20% in the valleys and 30s in the mountains with good
overnight recoveries.

&&

.CLIMATE...Based on the forecast high temperatures for Tucson over
the next 3 days, June 2024 will join July 2023 & June 2013 as the
only calendar months on record to record triple-digit high
temperatures every day.

&&

&&

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

$$

Tetrault

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