textproduct: Reno

KEY MESSAGES

* A warming trend continues through the weekend with near record high temperatures most likely from Sunday through Tuesday.

* Dry conditions are expected through early next week with typical afternoon west breezes most days.

* Some cooling returns by mid-late next week with isolated shower chances and periods of breezy winds.

DISCUSSION

Forecast guidance continues to show an upper ridge over the W CONUS today and into tomorrow. A shortwave trough is seen moving through the PacNW on Sunday though keeping the general ridging pattern intact over the CWA. The upper ridge then will restrengthen going into the beginning of the work week with a closed low traveling through the Pacific behind the ridge. With this pattern aloft, the warming trend looks to continue at least through the beginning of next week. Today's daytime high temperatures will be similar if not a degree or two warmer to those experienced on Friday which were around 10-15 degrees above normal. However, near record to record daytime high temperatures across the region expect to start next week around 15-20 degrees above seasonal normals (Please see the Climate section for a list of the current temperature records at our two climate sites: Reno, NV and South Lake Tahoe, CA). Generally, the temperature forecast for Sunday through Tuesday shows highs in the upper 80s to lower 90s range in NE CA and W NV valleys while the Sierra communities will range between the upper 70s and the lower 80s. The latest NWS HeatRisk forecast shows an areawide minor category of HeatRisk early next week with portions of W NV being in the moderate category. Please take the time now to prepare for this heat especially if you have outdoor plans and are sensitive to heat.

The ridge pattern will also allow for dry conditions to prevail this weekend and into early next week. Increased daytime heating could allow for a brief pop-up shower, but chances look to be less than 10%. Models do not really highlight any particular area at this time with the "best" chances. Light winds are expected today, then typical zephyr-type west breezes (gusts up to around 25 mph) return each afternoon on Sunday through Tuesday.

The upper air pattern looks to change by Wednesday as the resident ridge moves east with the aforementioned low making landfall on the west coast. There is some uncertainty in the evolution of this low through the rest of the week as some models have the low opening up into a trough as it makes landfall while the others continue it as a closed low. But overall, this pattern will cause temperatures to begin a slow cooling trend while staying above seasonal normals going through the latter half of the week. Precipitation chances may return to the region on Wednesday onward, but there is low confidence in details at this time due to the model uncertainty. Some model scenarios even show an increased potential for showers and thunderstorms by Thursday or Friday, so will be monitoring if they become more favorable going forward. -078

AVIATION

VFR conditions are expected today and tonight at all area TAF sites with generally light winds. There is around a 20% chance that KTRK could see fog develop between 10-15Z this morning, which could cause sub-VFR conditions. Will monitor and amend TAF if confidence increases. While dry conditions prevail, a warming trend also continues through the beginning of next week which could potentially bring density altitude concerns. -078

CLIMATE

Current record high temperatures for Reno, NV that have potential to be broken or tied next week:

May 10: 88 F, set in 1934. May 11: 90 F, set in 2001 and 2013. May 12: 89 F, set in 1959 and 2013.

Current record high temperatures for South Lake Tahoe, CA that have potential to be broken or tied next week:

May 10: 75 F, set in 2025. May 11: 78 F, set in 2013. May 12: 79 F, set in 1988 and 1996.

REV Watches/Warnings/Advisories

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