textproduct: Reno

KEY MESSAGES

* Showers with embedded lightning will arrive this afternoon and evening along the Sierra and later today over Pershing and Churchill counties.

* A slow moving storm will bring widespread wetting rains and high elevation snow to the region Wednesday and Thursday.

* Cool but mainly dry Friday into the weekend. An unsettled pattern could bring a storm or two next week.

DISCUSSION

An upper low with the center of circulation spinning off the central California coast is beginning to filter clouds and showers into the Sierra for this afternoon. This is the preview of the anticipated storm that will shift our weather pattern across CA and NV to a cooler, wetter pattern. The height of this storm is targeted to arrive for Wednesday and Thursday, when widespread showers and high-elevation snow will impact the area.

.REST OF TODAY.

* WINDS: Today's winds will be lighter overall compared to Monday's winds, although Mono and Mineral counties will see gusts of 30-40 mph this afternoon.

* PRECIPITATION: Light rain showers with embedded lightning will move across the eastern Sierra, streaming from the southwest. It will impact the Sierra mountains first, then the robust moisture plume will advance across west-central Nevada and northeast California. Rain totals for today will remain below 0.10".

.WEDNESDAY->THURSDAY: THE MAIN EVENT.

* PRECIPITATION: A widespread wetting rain event (75-80% chance for >0.25 inches of rain along the Sierra Front, then east of US-95 a 60-70% chance for >0.25 inches of rain) begins late Wednesday morning near the eastern Sierra and then spreads to the north and east. Embedded thunderstorms may produce locally heavy rainfall (1-2" totals possible) and even some small hail. Rain will help to reduce the fire potential across NE CA and W NV as well as help to settle dust. However, localized heavy rainfall may bring localized flooding in poor drainage areas and burn scars such as the Hawk, Bull and Bug fires. Passes such as Ebbetts, Tioga, Sonora, Carson and Mt. Rose Hwy have a 40-70% chance for up to 4" of fresh snowfall, with a 25% chance for up to 8 inches of snow at Tioga Pass. Higher amounts will be limited to the highest peaks in the Sierra.

* TEMPERATURES: With ample cloud cover limiting solar radiation for Wednesday, we will see daytime highs across NE CA and W NV generally in the mid-to-upper 60s to near 70 degrees while Sierra locations will reach the 50s to near 60 degrees. Thursday, the colder air settles in, dropping daytime lows over NE CA and W NV into the upper 50s to near 60 as our neighbors in Sierra valleys will see upper 40s to mid 50s, elevation dependent.

* PREPARING FOR THE STORM: Expect slick road travel and slower commutes from Wednesday afternoon through Thursday. Now is a good time to prepare your vehicles for winter travel, as well as checking and clearing the gutters and storm drains for debris that may slow or inhibit the draining of water.

.WEEKEND & EXTENDED OUTLOOK.

* WEEKEND: Dry and cool with highs in the mid-50s for Sierra communities and lower-to-mid 60s at lower elevations which will bring our temperatures into seasonal averages.

* NEXT WEEK & BEYOND: Low-confidence potential for additional storms and heavier Sierra snowfall as we look to late October. HRICH

AVIATION

* TODAY: VFR conditions prevail with light easterly/southeasterly winds. Isolated showers after 21z for Sierra terminals and 00z for western Nevada terminals may cause brief periods of terrain obscuration.

* WEDNESDAY->THURSDAY: Widespread rain brings periods of MVFR/IFR conditions and terrain obscurations. Thunderstorm chances peak at 25-30% for Wednesday, dropping to 15-20% for Thursday. HRICH

REV Watches/Warnings/Advisories

NV...None. CA...Winter Weather Advisory from 11 AM Wednesday to 5 PM PDT Thursday CAZ073.