textproduct: Reno

KEY MESSAGES

* Warmer than normal weather prevails through the weekend with typical afternoon westerly breezes.

* Showers and isolated thunderstorms are possible this afternoon with better chances Friday afternoon.

* Increasing potential for stronger winds and critical fire weather conditions, showers and storms, and much cooler weather next week.

DISCUSSION

Warm weather continues today with daytime highs reaching the low 70s and low 80s, which about 5-10F above seasonal averages. Latest satellite obs show cumulus developing along higher terrain, but are struggling to acquire much vertical growth under subsident flow. However, steepening mid-level lapse rates and low-level convergence along the zephyr breeze will support a low to moderate (10-30%) likelihood of showers and isolated thunderstorms later this afternoon across NE California, the E Sierra, and far W Nevada. Stronger showers/storms will be capable of gusty outflow winds up to 40 mph, brief heavy rain and sudden temperature drops, and occasional lightning.

The potential for showers and thunderstorms peaks Friday afternoon as moisture quality improves and instability increases. Convection will focus across a similar area as today, but should begin earlier in the afternoon or perhaps in the late morning. Expect similar hazards with Friday's bout of convection. Moisture is displaced eastward over the holiday weekend, shifting the best potential for afternoon showers and thunderstorms to the near the OR border, the W NV Basin and Range, and Mono County.

Temperatures remain warmer than normal through the holiday weekend, when of which daytime highs will be in the mid to upper 70s/80s. Though tempting, be sure to avoid cooling off in lakes, rivers and creeks this holiday weekend as they are still running dangerously cold and swift (water temps in the upper 40s and 50s).

A more robust Pacific low is on track to impact the region early next week, increasing the potential for strong/gusty winds, showers/t-storms, and much cooler temperatures. Critical fire weather conditions are increasingly likely Monday afternoon across NW Nevada where gusty winds combine with low daytime humidity (more details in the fire weather section). Still some questions about the Pacific low's timing, but be prepared for a noticeable change in the weather next week.

-Salas

AVIATION

Showers and isolated thunderstorms will be the main concern today, focusing eastern Sierra terminals where chances are around 10-20%. Showers and storms may drift into KRNO-KCXP-KMEV, but odds are low (less than 10%). Sudden, strong wind shifts, brief heavy rain and MVFR conditions, and lightning are the primary concerns into the evening.

Thunderstorm chances increase Friday afternoon across a similar area, posing renewed impacts to aviation interests. Elsewhere, cumulus build-ups may result in mountaintop obscuration in the afternoon.

-Salas

FIRE WEATHER

A critical fire weather environment is increasingly likely to develop Monday afternoon from eastern Lassen County/the Surprise Valley into NW Nevada where strong winds couple with low daytime humidity. There is still some uncertainty in the continuity of receptive fuel beds, but recent fuel intel indicates that live fuel moisture in sagebrush is at record lows and more typical of late June in west-central Nevada. As such, details need to be sorted out but certainly worth close monitoring.

-Salas

REV Watches/Warnings/Advisories

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