textproduct: Reno

KEY MESSAGES

* Dry weather with unseasonably warm temperatures continues today with afternoon breezes.

* A cooler and wetter pattern starts tomorrow, with valley rain and high elevation snow chances during the latter half of the week.

* Isolated to scattered thunderstorms are possible Thursday and Friday, though confidence remains low on the extent of the impacts.

DISCUSSION

The axis of a weak ridge will be moving overhead today, allowing our region to stay dry and partly cloudy. This ridge will hang around for another day or so, until it starts to breakdown and a trough pushes its way in. Temperatures today and Wednesday will top out in the mid 70s for NE CA and W NV valleys and mid 60s for Sierra valleys. Typical afternoon gusts up to 25 mph out of the west will also be around through Wednesday.

As that trough approaches the West Coast Wednesday afternoon, there's about a 20-30% chance of showers (10% chance of lightning) along the Sierra crest from Tahoe northward, into NE CA and N Washoe County. Some CAMs are also showing some showers popping up in Mono County and moving northeast throughout the evening into Mineral County, but those chances are less than 20%. The positioning of the low off the coast puts NE CA right under an area of upper level diffluence, aiding the development of showers and thunderstorms. Right now the CAMs are showing anywhere from 200-600 J/kg of MUCAPE and 20-30 kt 0-6km bulk shear, just enough of the right ingredients to produce a couple non-severe thunderstorms.

Coverage and probabilities increase Thursday (25-40%) for the same areas. Friday, coverage increases to the whole Sierra crest from Mono County up to Lassen County. Friday currently has the highest chance (60-80%) for the Sierra Front (Reno, Carson, Minden) to see showers and thunderstorms (15-25% chance lightning), although Saturday may also have equal chances. This far out it's still a little too uncertain to tell. Temperatures will take a hit later this week as well, with high temperatures dipping down into the upper 50s for W NV valleys and upper 40s for Sierra valleys by Sunday. We'll know more as we get later in the week, but at it stands right now, expect a stormy pattern through Sunday.

-Justin

AVIATION

VFR conditions are expected once again for all area TAF sites today. Dry conditions persist today with KRNO/KCXP/KMEV/KMMH seeing afternoon gusts up to around 15-20 kts.

An approaching Pacific low changes the weather pattern on Wednesday causing rain and isolated thunderstorm chances (20-30%) in NE CA and far NW NV. The precipitation chances then increase and become more widespread along the Sierra crest and into the Sierra Front through the remainder of the week. Isolated to scattered thunderstorms are possible Thursday and Friday along with potential Sierra snow showers going into the weekend. -078/Justin

REV Watches/Warnings/Advisories

NV...None. CA...None.