Bisbee Junction, Arizona Weather Forecast Discussion

725
FXUS65 KTWC 180912
AFDTWC
Area Forecast Discussion
National Weather Service Tucson AZ
212 AM MST Thu Sep 18 2025
.SYNOPSIS...Moisture has moved into the region which will lead to
scattered showers and thunderstorms today through Friday with
diminished thunderstorm chances over the weekend. Temperatures
near to just below normal into the weekend before warmer and drier
weather returns next week.
&&
.DISCUSSION...Southeast Arizona is under mostly cloudy skies with
a few weak showers visible on radar. Aloft the upper level
remnants of Mario are just off the coast of southern California
and high pressure is centered over north central Mexico. Anomalous
moisture is in place with PWAT values 120-180 percent of normal
from east to west respectively. This moisture will be in place
through tomorrow. The low will move north and a little eastward
through the day tomorrow and Friday. This will lend upper level
support to showers and thunderstorms with the best synoptic scale
support just to the west in Yuma County and southern California.
Today expect another round of scattered showers and thunderstorms
starting this afternoon and continuing into the evening. The main
threat will again be heavy rainfall leading to localized areas of
flash flooding. Some HREF members keep convective activity going
overnight thanks to the jet that will be over the region. Right
now this activity looks to be favored over Pima County, then
becoming more widespread as the sun comes up Friday morning.
Shower and thunderstorm activity then continues into Friday
afternoon. Event total rain looks to be highest along the
international border and in the Sky Islands with 2 day rain totals
1"-3" possible. Expect flowing washes and rivers especially where
soils become saturated leading to more runoff. Temperatures will
be a few degrees below normal thanks to the cloud cover and
moisture.
This weekend moisture begins to decrease, but will still be above
normal. However the area of high pressure currently to the south
moves northward and southeast Arizona loses its upper level
support for storms. As a result NBM PoPs are 10-20 percent both
days mainly over the higher terrain. Temperatures begin to
increase becoming 2-3 degrees warmer than today and Friday.
Early next week the high keeps nudging northward, but ensembles
also bring a closed low south into southern California with
another low in the Great Plains and Midwest. This sets up an omega
block over the western U.S. For Arizona this will slowly dry us
out with temperatures climbing above normal. Lingering moisture
will lead to slight chance (15-20 percent) PoPs Monday with dry
conditions expected thereafter. Tucson could see triple digit
highs by the middle of next week.
&&
.AVIATION...Valid through 19/12Z.
BKN-OVC clouds 6k-10k ft AGL and BKN-OVC layer AOA 18k ft AGL
thru the valid period. Scattered TSRA possible after 18/19Z
through the evening. Some overnight convective activity will be
possible, but confidence is low on terminals being affected. With
showers and thunderstorms, expect locally heavy rainfall and
erratic winds up to 35 kts. Other than thunderstorm driven winds,
SFC winds will be from the south southwest 5-10 kts in the
afternoon and evening becoming variable less than 7 kts at other
times. Aviation discussion not updated for TAF amendments.
&&
.FIRE WEATHER...Above normal moisture is in place leading to min
RH between 20-40 percent through the weekend. Expect scattered
shower and thunderstorm chances (30-60 pct chance) today and
Friday, then diminished thunderstorm chances this weekend. Heavy
rainfall will be the main threat. Dry conditions return next
week. 20-foot winds will be 8-12 mph with some afternoon/early
evening gusts to around 20 mph over the next week with normal
diurnal patterns through the weekend.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Hardin
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NWS TWC Office Area Forecast Discussion