textproduct: Reno

KEY MESSAGES

* Critical fire weather and hazardous lake conditions today due to strong southwest winds.

* A strong cold front will be arriving for Sunday, bringing much colder temperatures, rain showers and mountain snow showers that may linger into early next week.

* Moisture associated with Tropical Storm Rachel will boost shower chances.

DISCUSSION

Evidence of the inbound frontal boundary is showing up across central Oregon on the satellite returns this morning, soon to take aim at the northern borders of California and Nevada. Winds are already beginning to pick up along the ridges, with southwest winds increasing through the day today. Lower valleys will see wind gusts ranging 35-45 mph, while the Sierra ridges will see gusts 70-80 mph. When coupled with low relative humidities, it will bring about critical fire weather conditions today. Winds will also create choppy lakes and travel troubles, so keep that in mind if you have travel or recreation plans for today. Temperatures will also take a tumble from recent daytime highs, western Nevada could see low 70s while Sierra communities will have to settle for low 60s. This will signal the beginning of the cooldown associated with the passage of this front.

For Sunday, the chill is on! Western Nevada valleys will struggle to make it into the low to mid 60s while Sierra locations will only reach into the low 60s to mid 50s. As this trough digs eastward, another feature associated with the remnants of Tropical Storm Rachel will help to boost shower chances, mainly south of I-80. Chances range from 50 to 80%, with the greatest chances along the Sierra and across the western Nevada Basin and Range. One issue we are watching is the relative warmth from this tropical system overriding the colder, denser air from the frontal passage has caused some fluctuation in snow levels. Recent NBM runs show snow levels around 8500-9500 feet to start Sunday, falling to around 6500- 7000 feet by Monday morning. Overnight temperatures Monday and Tuesday nights in the Sierra will support any snowfall that does accumulate.

By Tuesday, the moisture will move off to the east, as we clear out into the afternoon. Once the system exits, we will start to resume a drying and warming trend that will carry us through the rest of the work week and into the following weekend. HRICH

AVIATION

* Increasing southwest winds today will bring gusts 25-40 kts to Sierra and Sierra Front terminals. Expect LLWS and turbulence to accompany the wind gusts. Tonight, KMMH has a 20% chance to see showers.

* For Sunday, shower chances spread across the region, with all terminals seeing chances. HRICH

FIRE WEATHER

The seasons first potent cold front will bring increasing southwest winds Saturday as it moves through NE California and W.Nevada. Winds combined with low humidity and dry conditions are expected to produce periods of critical fire weather conditions.

SATURDAY: Winds peak Saturday afternoon and evening, with widespread gusts of 35-45 mph mainly south of I-80. Humidity will increase across NE California and far NW Nevada, while areas south of I-80 may see continued elevated concerns with a more marginal minimum RH of 15-20% on Saturday afternoon. Red Flag Warnings are in effect today due to strong winds and low RH for portions of W.Nevada including the Sierra Front and the E.Sierra from E.Alpine County into Mono County.

SUNDAY ONWARD: Behind the front, highs will drop 20-25 degrees from Friday to Sunday, reaching the upper 50s/low 60s across W.Nevada and low 50s in E.Sierra communities. Wetting rain potential increases Sunday-Monday, mainly south of I-80, as remnant moisture from Tropical Storm Rachel moves northward. The moistures track and precipitation totals still show higher uncertainty, but the overall trend has been wetter.

-McKellar/Justin/HRICH

REV Watches/Warnings/Advisories

NV...Red Flag Warning from 11 AM this morning to 9 PM PDT this evening NVZ420-421-423-429.

Lake Wind Advisory from 5 AM early this morning to 11 PM PDT this evening NVZ002>004.

Lake Wind Advisory from 11 AM this morning to 11 PM PDT this evening NVZ001.

CA...Red Flag Warning from 11 AM this morning to 9 PM PDT this evening CAZ274.

Lake Wind Advisory from 5 AM early this morning to 11 PM PDT this evening CAZ072.

Lake Wind Advisory from 11 AM this morning to 11 PM PDT this evening CAZ073.