FXUS65 KTWC 032236

Area Forecast Discussion
National Weather Service Tucson AZ
335 PM MST Fri Apr 3 2020

.SYNOPSIS...Dry conditions and warm daytime temperatures through
Tuesday. A weather system may bring a few showers as early as
Wednesday, although somewhat better rain chances will prevail late
next week with cooler temperatures.


.DISCUSSION...IR/visible satellite imagery and surface observations
depicted clear skies across western Pima county this afternoon.
Meanwhile, scattered cumuloform clouds were noted elsewhere across
southeast Arizona, and fairly thick cirriform clouds were also
moving across southeast sections of this forecast area. Expect the
high-based cumulus clouds to dissipate this evening with the loss of
daytime heating. Otherwise, clear skies favoring west to north of
Tucson, and mostly clear skies favoring southeast locales later
tonight and the rest of this weekend.

Various 03/12Z numerical weather prediction models depict a fairly
deep upper low to be centered near the central California coast
around midday Monday. The upper low is generally progged to slowly
dig southward to near the southern California coast by midday
Wednesday. For this forecast issuance, appears that precip-free
conditions will prevail through Wednesday.

Precip chances increase Wednesday night and particularly Thursday as
the upper low ejects northeastward into northern Arizona. Thus,
isolated showers Wednesday night followed by isolated to scattered
showers on Thursday. The best coverage of showers will be north of
Tucson with lesser chances across southern portions of the forecast
area. Thereafter, timing differences continued to exist between the
GFS/ECMWF regarding the eastward progression of the filling upper
trough. Per coordination with neighboring WFO`s, have maintained
isolated showers next Friday especially north of Tucson. The general
summary regarding this system appears to be a relatively light
precip-event for southeast Arizona, with the main impact ultimately
being markedly cooler temperatures, particularly next Thursday and


.AVIATION...Valid through 05/00Z.
FEW-SCT clouds mainly near 15k ft MSL becoming SKC-FEW clouds above
25k ft MSL (cirrus especially southeast of KTUS) this evening and
continuing into Saturday afternoon. Surface wind swly/wly 10-20 kts
with gusts near 30 kts into early this evening and again Saturday
afternoon. Surface wind variable in direction under 12 kts at other
times. Aviation discussion not updated for TAF amendments.


.FIRE WEATHER...Dry conditions through Tuesday. A few showers may
develop Wednesday west to north of Tucson, then isolated to
scattered showers across much of the area Thursday. A few showers
may linger next Friday mainly north of Tucson. Expect seasonably
gusty afternoon winds at times through the forecast period. Areas of
predominately dead grass would be susceptible to high rates of
spread during the afternoon peaks of winds and heating.





Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson

NWS TWC Office Area Forecast Discussion