textproduct: Reno

KEY MESSAGES

* Gusty southwest winds will bring a period of critical fire weather conditions and lake recreation impacts to parts of northeast CA, northwest and far western NV Saturday.

* Showers and isolated thunderstorms return this weekend across parts of the eastern Sierra and western NV, with the highest chances on Saturday.

* Near seasonal temperatures prevail through next week with overall dry conditions and afternoon breezes, which may increase for a day or two around the middle of next week.

DISCUSSION

A swath of mid-high level clouds continues to track northward across northern CA-western NV today, leading to a slight cooling compared to the past couple of days. Slight instability may lead to a few showers across west central NV east of US-95 through the rest of this afternoon, although the chance for lightning is 10% or less. Elsewhere, winds edge upward a bit with gusts 25-30 mph across parts of northeast CA and western NV through early this evening.

For Saturday, we'll see winds increase as an upper level trough associated with a low pressure off the Pacific NW coast passes across northeast CA/northwest NV. This will bring lake recreation impacts for northeast CA and far western NV, where Lake Wind Advisories have been issued, and increased fire concerns with further details in the Fire Weather section below. Meanwhile, an increase in instability from the eastern Sierra of Mono County northward across areas of western NV will lead to 15-35% chances of showers and isolated thunderstorms. The best chances in western NV favor Lyon, Mineral, Churchill and Pershing counties, but a few cells could build a bit farther west across eastern parts of Storey, Carson City and Douglas counties. This activity is projected to start as early as 1-2 PM, and linger until 8-9 pm for far eastern portions of the Basin and Range, with stronger storms producing outflow gusts up to 45 mph, brief heavy rainfall, small hail and several lightning strikes.

By Sunday, the winds trend downward to more typical gusts to near 25 mph. Shower and thunderstorm coverage decreases compared to Saturday, although isolated showers with 10-15% chance of lightning remain for Sunday afternoon, mainly in west central NV and eastern Mono County.

For next week, the ensemble guidance is trending to a drier scenario while temperatures remain near or slightly above late August averages, with highs mainly 90-95 for lower elevations and lower 80s for Sierra communities. Typical afternoon breezes are expected, although a weak shortwave brushing across the Pacific NW may kick winds up a bit around the Tuesday-Thursday time frame, depending on the timing of this system's passage. MJD

AVIATION

* VFR conditions prevail with widespread mid to high level clouds through much of this weekend. Shower/thunder chances return this weekend mainly on Saturday, but storms have a 10% or less chance of affecting the main terminals.

* SW-W wind gusts 20-25 kts at the main terminals today through 02-04Z. SW winds increase Saturday with gusts near 30 kt at the main terminals, except a bit less at KTRK/KTVL. By Sunday, winds decrease to similar levels as today. MJD

FIRE WEATHER

* Wind gusts of 25-30 mph this afternoon will bring isolated periods of elevated fire weather conditions across northeast CA and northwest NV, extending southward to near the Reno area.

* The greater fire weather concerns arrive on Saturday from late morning through the evening, as an upper trough passage increases wind gusts to the 30-40 mph range across northeast CA, northwest NV, and the Northern Sierra Front. While humidity values aren't exceedingly low (minimums 12-18%), most of these areas did not receive much rainfall last week, resulting in a greater extent of dry vegetation where fire could spread more quickly when the winds pick up. Therefore we have issued Red Flag Warnings for these areas, so be extra cautious and fire safe, avoiding outdoor recreation or work activities that could spark any fires. * From Sunday through next week, afternoon breezes continue but at lower speeds compared to Saturday. The next time period to watch could be as soon as next Tuesday or Wednesday, when winds potentially trend upward again, while afternoon humidity decreases as a dry air mass settles in. MJD

REV Watches/Warnings/Advisories

NV...Red Flag Warning from 11 AM to 11 PM PDT Saturday NVZ420-458.

Lake Wind Advisory from 11 AM to 11 PM PDT Saturday NVZ003.

CA...Red Flag Warning from 11 AM to 11 PM PDT Saturday CAZ270-278.

Lake Wind Advisory from 11 AM to 11 PM PDT Saturday CAZ071.