textproduct: Reno

KEY MESSAGES

* Isolated showers and thunderstorms are possible today, mainly in Churchill, Mineral, and Mono Counties.

* While smoke from the Hawk Fire may continue in the Reno/Sparks metro area today, impacts may decrease with breezy winds and better ventilation.

* Increased winds will bring elevated to critical fire weather conditions and potential recreational impacts on Wednesday through Saturday.

DISCUSSION

For today, the latest RAP analysis of the upper air pattern shows the CWA with a southwesterly flow aloft and still being underneath the western portion of a high pressure ridge over the Southwestern CONUS today. Another feature to mention is a PacNW low which is projected to move closer to the WA/BC coast through the day. With this low in place, models are showing slightly breezier SW winds today within the region with gusts up to around 25-30 mph. These winds will continue elevated fire weather conditions in NE CA and NW NV today. Forecast guidance is also showing around a 15-25% chance for isolated showers and thunderstorms within Churchill, Mineral, and S. Mono Counties between 2-8 PM. Forecast soundings show an inverted-V shape with MUCAPE values between 100-200 J/kg and DCAPE values over 1000 J/kg, so thunderstorms will be capable of producing gusts up to around 45-50 mph today. Forecast PW values are between 0.6-0.8 inches, so brief periods of heavy rainfall could be possible though flooding is not anticipated to be a threat as storms that occur will be moving quickly and short lived. The remainder of the region shows signs of staying on the dry side.

While the Hawk Fire may continue to generate smoke within the region especially near the Reno-Sparks area, the latest HRRR run of the near-surface smoke product does not show increasing smoke concentrations today. This may be due to better ventilation with breezier winds, but cannot rule out some morning haze when lighter winds prevail. It is interesting to note that the HRRR is showing potential smoke in NE CA from the Timber Fire burning on the CA coast early today. Please continue to monitor AirNow.gov for the latest air quality conditions and forecast information in your area.

Going forward through the rest of the week, forecast guidance is showing the aforementioned PacNW low moving closer to the BC coast on Wednesday, making over BC on Thursday, and continuing to trek into SW Canada going into the weekend. This causes the upper jet over the CWA to strengthen even more which will translate to gusty winds when they mix down to our surface here. The forecast is showing wind gusts up to 35 mph (up to 40 mph in wind prone areas) on these days, which will lead to critical fire weather concerns (see Fire Weather Section for more details) as well as potential recreational and travel impacts within the region during the latter half of the week. Cannot rule out some potential diurnal showers on Wednesday in W NV as well, but chances look to be low (<15%) at this time. The GFS shows the best chance for precipitation for the rest of this week being on Friday when a potential weak cold front passes through the region. Daytime high temperatures drop slightly to the middle to upper 80s in the NE CA and W NV valleys with Sierra Communities being in the 70s going through the weekend. Will continue to watch to see if more models agree with the GFS going forward. Beyond this, extended guidance does point to dry conditions early next week at this time. -078

AVIATION

VFR conditions are expected at all area TAF sites today and tonight Surface winds in the region gusting up to between 20-25 kts are forecast between 25/17Z-26/03Z. The latest HRRR smoke product does not show much impact from Hawk Fire smoke today compared to the previous days, but cannot rule out slightly reduced visibilities near the fire in Washoe County. Not anticipating flight rules to be reduced at this time due to smoke at KRNO, but will continue to monitor in case this changes.

As for precipitation chances today, there is a 15-25% chance for isolated showers and thunderstorms in Churchill, Mineral, and S. Mono Counties between 25/21Z-26/04Z. Lesser precipitation chances are seen in the NV Basin and Range on Wednesday afternoon. -078

FIRE WEATHER

Breezy SW winds with gusts up to around 25-30 mph and RH reductions of 15-25% will support elevated to isolated critical fire weather conditions this afternoon across the Sierra Front and NE CA, including the Hawk Fire. Tuesday night RH recoveries in these areas are forecast to be between 35-50%.

The latest SPC Fire Weather Outlook shows a 40% chance for critical fire weather due to wind and low RH in NE CA and NW NV through the rest of the week with the Friday showing a slight decrease in NW NV coverage. The forecast shows increased winds with gusts upwards of 35 mph (40 mph in wind prone areas) mainly for the Sierra Front and NE CA Wednesday through Saturday. Currently, days with the most widespread critical fire weather conditions in these areas looks to be Wednesday, Thursday, and Saturday. Please continue to watch for further updates in case fire products need to be issued. -078/Justin

REV Watches/Warnings/Advisories

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