textproduct: Reno

KEY MESSAGES

* Unseasonably warm, near record temperatures continue for this afternoon.

* Cooler temperatures, gusty winds, rain, and mountain snow return on Monday with impacts to recreation and travel, plus snow levels down to Sierra Passes by Thursday.

* Warmer and drier weather with gusty NE ridgetop winds return on Friday followed by lighter winds Saturday.

DISCUSSION

* This is our last day of record to near record high temperatures across the region for this historic March heatwave. Afternoon temperatures will rise well into the 70s for western NV and northeast CA; while mid-60s will be common in the Sierra valleys. Otherwise, westerly winds will start to gust upwards 20-30 mph through the early evening, and clouds associated with the incoming system will begin to increase across the region into tonight. There is a slight 10% chance of light rain this afternoon in Mono County between 1-4pm. Anything that hits the ground will be light. * The strong, persistent high pressure ridge that has been over the western US for weeks is finally breaking down on Monday, ushering in a series of shortwave troughs through the Pacific Northwest. For Monday, temperatures will fall by around 3-6 degrees, but are still above average for the final days of March. In addition to the cooldown, westerly winds will increase as the day progresses. Wind gusts upwards of 30-40 mph will be common in the western NV valleys and local area lakes, with gusts between 50-60 mph along the Sierra ridges. As for precipitation, the high-resoultion ensembles show likely (50-70%) showers moving into Lassen, the Surprise Valley, and northern Washoe by 3-5pm, with snow levels around 8,000 ft. Other areas (minus a ~20% precipitation chance in northern Pershing County) should be mostly dry. * By Tuesday, another shortwave trough moving into the region will allow Monday's surface cold front to continue its southward track. This will lead to likely (>60%) periods of rain throughout the Sierra, with snow levels between 7,500 to 8,000 ft before colder air moves in Wednesday. Tuesday's high temperatures will finally return to seasonal readings. * For Wednesday into Friday, a closed-low will move through the Great Basin. These lows are notoriously hard to predict several days out during the spring transition season, therefore we continue to have uncertainty about precipitation quantities, and snow levels. However, the current trend still favors a period much cooler temperatures, Sierra rain and snow showers, along with gusty winds throughout the region. Although this does not currently look like a strong system, it's a very big change from our recent streak of summer-like temperatures. By the weekend into the start of next week, we clear out and warmup as another ridge moves back into the western US. -McKellar

AVIATION

* For the remainder of today, expect widespread VFR conditions along with an increase in mid to high level clouds. Typical breezy afternoon west winds persist with gusts to 15-25 kts. There is a 10% chance of light rain near KMMH between 20-02Z today.

* An unsettled weather pattern starts Monday and continues for much of the upcoming week. This includes the potential for reduced CIGS/VIS in precipitation and mountain obscurations as well as LLWS/mountain wave turbulence. -McKellar

REV Watches/Warnings/Advisories

NV...Lake Wind Advisory from 11 AM to 10 PM PDT Monday NVZ002-004.

CA...Lake Wind Advisory from 11 AM to 10 PM PDT Monday CAZ072.