452
FXUS65 KREV 121020
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
320 AM PDT Wed Jun 12 2024

.SYNOPSIS...

Near record to possibly record temperatures are expected once again
today and tomorrow for the region. A few showers and isolated
thunderstorms will be also possible for areas along and south of
US-50 during the late afternoon and evening hours for both days
as well. Drier, cooler, and breezier conditions are expected with
the arrival of a dry cold front this weekend.

&&

.DISCUSSION...

The latest RAP analysis of the upper air pattern displays a large
ridge over the western CONUS with a cutoff upper air low off the
coast of the Baja Peninsula. Current satellite imagery along with
surface observations report dry conditions with relatively light and
variable winds underneath clear skies across the region. Going
through the rest of today, models show the broad ridge remaining
over the CWA with the southern low beginning to move slightly
northeastward yet still off the coast of the northern Baja
Peninsula. On Thursday, forecast guidance forecast the low to move
northeastward across southern CA and then into southern NV by
Thursday night as an upper air trough begins to make its appearance
in the Pacific Northwest. At the surface, the main story still
continues to be the near record to record heat in the region.
Western NV looks to see daytime highs in the 90s with some portions
in the hotter valleys reaching the lower triple digits. When looking
at the latest NBM probabilities for daytime high temperatures
reaching 100F or more, the Reno/Tahoe International Airport (KRNO)
currently has a 30% chance for a triple digit max today. High
temperatures for Thursday look to be a degree or two cooler, but
will still be unseasonably hot being 10-15F above normal. The latest
HeatRisk map show widespread moderate risk to heat today and
tomorrow with some isolated major risk in western NV, so please
continue to take precautions to deal with this heat.

Models also show diurnal heating allowing for some precipitation
chances (10-20%) for areas within the CWA along and south of US-50
today once again during the afternoon and evening hours. The same
areas may see similar chances chances tomorrow due to enhanced
diffluence associated with a closed low tracking across the
southwestern U.S. These storms may be capable of small hail, brief
heavy rains, and gusty outflow winds (>45 mph).

On Friday, forecast guidance shows an upper air trough moving into
the Pacific Northwest and pushing the ridge feature off to the east
over the Great Plains by late in the day. With this going on aloft,
the CWA can expect a dry cold front passage which will usher in
southwesterly winds gusting up to around 25-35 mph during the
afternoon with the potential for up to around 40 mph in wind prone
areas. This may create some choppy conditions across area lakes
along with cross wind issues for high profile vehicles Friday
afternoon. Temperatures in the CWA look to start a slight cooling
trend starting on Friday with this cold front as well. There may be
some critical fire weather concerns for some portions within the CWA
on Friday as well with the dry airmass allowing for relative
humidity values to drop during the day along with these expected
winds. Will continue to monitor this as well as the fuel status and
update the forecast as needed.

For this weekend and into the start of next week, model guidance
shows the CWA being under the eastern portion of the upper air
trough`s base on Saturday before the axis of the trough passes over
the CWA on Sunday night. Ensemble guidance then shows the CWA under
the base of the trough on Monday and Tuesday. Currently, the
forecast calls for the cooling trend to continue through the weekend
and into Monday before models hint at a possible rebound to warmer
temperatures on Tuesday. As for the longer term precipitation
chances, the CWA looks to stay mostly dry over the weekend with long
term models still in disagreement with chances to begin next week.
Will continue to monitor future model runs and update the forecast
as needed. -078

&&

.AVIATION...

VFR conditions are expected once again today for all of the region
TAF sites with winds gusting up to around 20-25 kts during the
afternoon hours. Winds then look to decrease starting in the evening
and going into the night. There also is a slight chance (10-20%) for
isolated showers and thunderstorms in the vicinity of KTVL, KMEV,
and KMMH during the late afternoon and evening today, but not
anticipating impacts to these terminals at this time. Density
altitude impacts may be possible still through Thursday as afternoon
high temperatures around 15-20 degrees above average. -078

&&

&&

.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&

$$