533
FXUS65 KREV 030914
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
214 AM PDT Mon Jun 3 2024

.SYNOPSIS...

An area of low pressure will bring light showers, increased cloud
cover, cooler temperatures, and increased breezes through this
evening. A significant warmup occurs mid to late this week, with
highs nearing the century mark in lower western Nevada valleys.
Afternoon thunderstorms will also be possible from Wednesday through
next weekend.

&&

.DISCUSSION...

Current GOES-18 infrared and water vapor satellite imagery show a
vigorous upper low moving ashore over northwestern Washington and
southwest British Columbia this morning. Increased moisture along
the southern fringe of the polar front jet will overspread our
region this morning. The upper-level shortwave trough and the
attendant cold front associated with this weather system will push
south across the region today, cooling temperatures into the
upper-70s to low-80s across western Nevada and upper-60s to
low-70s in the Sierra. Light showers will also be possible into
the early afternoon mainly north of US-50, as the pre-frontal
trough swings through northern Nevada. Westerly winds will also
increase this afternoon and evening with sustained speeds of 15-25
mph and gusts to 35 mph expected across lower elevations and
55-65 mph gusts this morning across Sierra ridges. Lake Wind
Advisories are in effect for Sierra and western Nevada lakes
through this evening. Increased relative humidities will hinder
most fire weather concerns associated with the increased wind
speeds.

Tuesday into at least Saturday, a moderately anomalous upper-level
ridge will build over the Great Basin and Pacific Northwest, heating
our region, with highs topping out in the mid-to-upper 90s for lower
elevations and 80s for the Sierra. NBM probabilistic guidance has a
25-35% chance of lower valley locations in Pershing and Churchill
counties hitting the century mark Thursday. Heat risks will be
moderate, so limit outdoor activities if you can. Streams will
continue to run fast and cold, so take precautions when hiking and
camping near waterways. Increased mid-to-upper level moisture from
the Gulf of California will surge northward around the western
periphery of the ridge, bringing increased chances for showers and
thunderstorms each afternoon and evening Wednesday through Saturday.

Long-range ensemble guidance hints at the upper-level ridge axis
moving over the northern Rockies early next week, which would cool
our region by about 5 degrees Sunday, with highs in the upper-80s to
low-90s across the lower elevations and upper-70s to low-80s in
Sierra valleys. However, these temperatures will still be roughly 10
degrees above average. Some model guidance shows a shortwave trough
pushing across the region early next week, which would keep the
potential for afternoon thunderstorms around. However, the depth and
placement of this upper-level trough will modulate where convective
development occurs.

-Johnston

&&

.AVIATION...

VFR conditions continue today, with thickening mid-to-high-level
clouds overspreading the region. Areas mainly north of US-50 could
see lowered CIGs, which may generate mountain obscurations. Brief
-SHRA will also be possible between 14-22z. Westerly winds will
increase across all regional terminals, with gusts approaching
25-30 kts from 18Z-03z Tuesday. FL100 winds will also increase,
with gusts around 50-55 kts. Light to moderate turbulence and low-
level wind shear are also expected.

A heatwave is expected Wednesday into the weekend, with highs in the
mid-to-upper 90s across lower elevations of western Nevada and
northeastern California and 80s in the Sierra. These increased highs
will bring density altitude concerns for naturally aspirated
aircraft. Density altitude at KTRK Wednesday-Friday afternoon
could approach 7500-8500 ft MSL (1500-2500 ft above field
elevation). We will also see increased chances for showers and
thunderstorms each afternoon Wednesday into the weekend.

-Johnston

&&

.REV Watches/Warnings/Advisories...
NV...Lake Wind Advisory from 9 AM this morning to 5 PM PDT this
     afternoon NVZ002.

     Lake Wind Advisory from 11 AM this morning to 8 PM PDT this
     evening NVZ003.

     Lake Wind Advisory from 1 PM this afternoon to 8 PM PDT this
     evening NVZ004.

CA...Lake Wind Advisory from 9 AM this morning to 5 PM PDT this
     afternoon CAZ072.

&&

$$