Area Forecast Discussion
Issued by NWS Las Vegas, NV

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS65 KVEF 212142

Area Forecast Discussion
National Weather Service Las Vegas NV
242 PM PDT Fri Jul 21 2017

.SYNOPSIS...Drier air filtering into the area is decreasing
thunderstorm chances and helping temperatures warm a few degrees
through the weekend. Another round of monsoon moisture brings
increasing thunderstorm chances back to the entire area for early
next week.

.DISCUSSION...Today through Friday.

Rather stout moisture gradient across the area, roughly along I-15
in southern Nevada. While drier air has attempted to work into the
area, this has been tempered with mixing as moister air from the
midlevels has mixed down this afternoon. Any perturbation could
shift moisture back into portions of the area, yielding a below
average confidence in the precipitation forecast through the

Models are coming into better agreement for early next week with
high reestablishing near the four corners region with an easterly
wave working across northern Mexico, curving into the region.
Combined, these features will allow deep moisture to return to
the area. Confidence remains only moderate in the potential for
widespread thunderstorm activity beginning Sunday night through
Thursday, with the usual concerns over cloud cover and previous
activity/MCVs from central Arizona. However, with the eastern wave
coming near, and a shortwave just off the western US coast, ample
forcing will be present.

Somewhat drier air will likely begin to work into the area after
Tuesday...however the entire area will not likely be scoured out.
Additionally, southeast flow looks to redevelop late in the week,
so have made little change to the forecast during this timeframe.

.FIRE WEATHER...Monsoonal moisture shifts eastward for the weekend
with lingering moisture allowing for isolated showers and storms
across eastern Lincoln and Mohave counties. Critical RH values will
be likely each afternoon this weekend across Inyo, Esmeralda, Nye,
and San Bernardino counties but with no significant wind expected,
fire danger concern remains low. Increasing chances for showers and
storms is expected next week as a shift in the weather pattern
allows for moisture to stream northward across the region.

.HYDROLOGY...Creeks, streams and rivers in northern Inyo County have shown
decreasing flows over the last day and a half. However, some road
closures continue in the area. Bishop Creek Bypass and Big Pine
Creek Bypass continue to be utilized to minimize flows through
Bishop and Big Pine. Remember, never drive through flooded
roadways or around barricades. Also, pastureland or farmland
adjacent to creeks, streams or rivers could experience areas of
standing water.

.AVIATION...For McCarran...Winds will generally be southerly through
early this evening up to 10 knots with gusts around 15 knots.
However, direction could vary between 160 and 210 degrees. Winds
will become southwesterly later this evening with speeds up to 10
knots. Light northeast winds Saturday morning will gradually veer
around to southeasterly with speed generally under 10 knots.
Thunderstorms are not expected in or near the Las Vegas Valley but
are possible in the Peach Springs Corridor this evening and again
Saturday afternoon and evening.

For the rest of southern Nevada, northwest Arizona and southeast
California...Mainly southerly winds across the area through early
this evening then mainly diurnal winds tonight and Saturday morning
with south winds 5-15 knots developing again Friday afternoon.
Thunderstorm chances will be limited to mainly Mohave and far
eastern Lincoln Counties through early this evening and again
Saturday afternoon

.SPOTTER INFORMATION STATEMENT...Increasing monsoonal moisture
will bring increasing thunderstorm chances across the region next
week. Spotter activation may become necessary Sunday night through



For more forecast information...see us on our webpage: or follow us on Facebook and Twitter is the U.S. government's official web portal to all federal, state and local government web resources and services.