798
FXUS65 KREV 080933
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
233 AM PDT Wed May 8 2024

.SYNOPSIS...

Following a chilly morning, the region expects to see another dry
and breezy day today. A warming and drying trend ensues through the
latter half of the week, with above average temperatures expected
this weekend. The return of precipitation chances within the
region may be possible to begin next week.

&&

.DISCUSSION...

According to the latest RAP analysis, the CWA currently has a north-
northwesterly upper air flow being underneath the western portion of
an upper air trough with an upper air low over the Northern Plains
and an upper air high to the north of it over SK/MB. Current
satellite imagery and surface observations report generally light
and variable winds underneath clear skies across the region. Going
through the rest of today, forecast ensemble guidance shows the
CWA`s upper air flow veering to the north by the afternoon before
turning to the northeast as the CWA will be underneath the area
between a positively tilted ridge in the north/northeast and a
positively tilted trough to the east/southeast. At the surface, a
backdoor cold front is expected to pass through the region this
morning allowing for cool daytime high temperatures ranging from
the 50s in northeast CA and the Sierra Mountains to the lower 60s
in western NV. One concern looks to be around Lake Tahoe and the
Sierra Mountain areas to the east in CA as models are showing
around 5-7 mb pressure gradient across those areas especially in
the evening and going into the night with a surface low residing
in central CA. While the region expects to see some breezy
northeasterly surface winds during the day behind the cold front,
the placement of the aforementioned surface low along will allow
for gusty easterly winds during starting in the evening going
through the night that will cause Lake Wind Advisory criteria to
be met at Lake Tahoe during that time. While low temperatures
tonight generally look to be slightly warmer that the previous
night, areas around the Tahoe Basin and south into Mono County may
see near to below freezing lows once again tonight into tomorrow
morning. May want to consider continuing protecting the sensitive
vegetation at least for another night within these areas.

Going through the rest of the week, model guidance forecasts an
upper air low to develop over UT on Thursday that will move a bit
eastward over the NV/UT border on Friday. On Saturday, models
project the low to start to move over the Four Corners region with a
quicker progression seen in the GEFS compared to the ECMWF EPS
leaving the CWA underneath an upper air ridge residing over the
western half of the CONUS. With this upper air pattern, a warming
trend can be expected going into the weekend with daytime high
temperatures up to the lower 70s returning to the western NV
portions of the region on Thursday followed by highs up to the
middle 70s on Friday. By Saturday, high temperatures look to range
between around the 70 degree mark in the Sierra to around the 80
degree mark in western NV. Minimal precipitation chances are in
the forecast as well with not much cloud cover expected, so dry
conditions look to prevail going into the weekend.

As for next week, ensemble guidance shows the CWA staying underneath
the ridge on Sunday followed by a weak upper air trough passing
through central and southern CA on Monday and to the south of the
CWA on the beginning of Tuesday. By Tuesday afternoon, models
suggest another large upper air ridge beginning to move into the
Pacific Northwest that will cover the western third of the CONUS by
Wednesday. At the surface, it looks like daytime highs ranging
between the lower 70s to the middle 80s are on tap for the first
half of next week at this time. There does look to be some low
chances (up to around 20%) for isolated showers and thunderstorms
within the region on Sunday afternoon and evening with similar
chances for precipitation being seen on Monday for the southern half
of the CWA. Confidence in these precipitation chances continues to
be low to medium due to some inconsistency with the last few model
runs, so will continue to monitor this going forward. Tuesday and
Wednesday are currently forecast to be mostly dry. -078

&&

.AVIATION...

VFR conditions expect to prevail for all REV TAF sites throughout
the week with little to no cloud cover expected. A backdoor cold
front passage will cause a northeasterly flow today that will
persist into the afternoon with some breezy gusts around 20-25 kts
beginning in the late morning/early afternoon at the REV terminals.

Temperatures will continue to warm to above average into the
weekend, with chances for afternoon/evening isolated showers and
thunderstorms possibly increasing (around 10-20%) by Sunday and
Monday. However, forecaster confidence still remains low to
medium at this time. -078

&&

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

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

&&

$$