textproduct: Reno

KEY MESSAGES

* Dry showers and thunderstorms expected today with gusty outflow winds and possible new fire starts from lightning.

* Monsoonal moisture increases Monday, bringing wetter storms and possible flash flooding concerns through Tuesday.

* Storm chances continue for the eastern Sierra and Mineral County Wednesday through Friday, though some uncertainty remains.

DISCUSSION

Yesterday ended up being a hot one out there before the cloud deck rolled in. High temperatures across western NV ranged from 100-106F, just as anticipated. Lows tonight may still be warmer than usual and provide little relief, so we're keeping the Heat Advisory going through this morning for Pershing, Churchill, Lyon, and Mineral counties. While we did have elevated to near critical fire weather conditions, there were a few more fires that broke out yesterday. Most notably is the Elephant Fire, which is burning over the old Loyalton Fire burn scar from 2020. This morning, smoke has settled into the North Valleys and Spanish Springs areas, but not quite into the downtown Reno/Sparks area. If you're in those northern valleys and have an air purifier, you might want to bring it out of the closet if you're sensitive to smoke. As per the HRRR, smoke may settle into Reno later this morning and cause some haziness after sunrise.

Later today, light showers and isolated dry thunderstorms are possible across western NV and northeast CA as our monsoonal moisture surge kicks off. RHs this afternoon range from 20-40%, even under the heavier showers. QPF totals today are generally less than 0.1", though some spots in the Sierra from Tahoe southward may get up to 0.2". Since storms are moving from south- north, we may see an outflow boundary form over Mineral/Lyon counties and push north through the afternoon. Gusts from this could range anywhere from 40- 55 mph, and may kick up some dust.

Then on Monday, western NV is able to generate more potential energy from an influx of low-level moisture. The main concerns then shift to small hail, gusty outflow winds, and possible flash flooding if storms start to train. PWAT values increase from 0.5-0.6" on Sunday to 0.9-1.1" on Monday. The main area of concern for these storms remains south of I-80, though portions of northeast CA and north of I-80 can see some lighter showers and occasional lightning strikes. Much of the same action on Tuesday for all the same areas.

By Wednesday, the forecast becomes a little more uncertain. Long range models diverge around this time and have the low off the coast and the high pressure to our east in different spots. Just a difference of a few hundred miles will determine whether or not we get precip out in the Basin and Range. We'll have more detailed information as these storms get closer in time, but for now just be aware of the upcoming weather hazards early this week!

-Justin

AVIATION

Light showers and dry thunderstorm chances return to the Sierra by 22Z today with potential for showers at KMMH between Sun 22Z-Mon 03Z and at KTVL between Mon 00Z-03Z. Cloud bases today will hover around 10-12 kft, though possibly lower with mountain obscurations around heavier showers. Winds today will be fairly light out of the west with gust up to 15kt.

Heavier rainfall and stronger storms are forecast Monday and Tuesday. While sfc winds will remain light, gusty outflow winds near thunderstorms can't be ruled out.

-Edan/Justin

FIRE WEATHER

A monsoon moisture surge today through Tuesday will usher shower and thunderstorm chances back into the Eastern Sierra and western Nevada, along with much of the Southwest US. First round of storms today will be on the dry side with the potential for starts outside of wetter rain cores. QPF will be light today, with most areas receiving less than 0.1". Surface RHs today will struggle to exceed 40% across western NV, even with a shower overhead. RHs may get a little higher in NE CA this afternoon, but QPF will remain low.

Storms will pose less of a fire risk Monday and Tuesday due to increased monsoonal moisture, higher QPF, and slower storm motions.

-Justin

REV Watches/Warnings/Advisories

NV...Heat Advisory until 8 AM PDT this morning NVZ001-004.

CA...None.