Area Forecast Discussion
Issued by NWS Reno, NV
Issued by NWS Reno, NV
351 FXUS65 KREV 190924 AFDREV Area Forecast Discussion National Weather Service Reno NV 224 AM PDT Thu Sep 19 2024 .SYNOPSIS... * A low pressure system will bring scattered showers and thunderstorms today mainly south of I-80, with snow in higher Sierra elevations. * Well-below average temperatures continue today, followed by near-average temperatures Friday through the weekend. * Quiet fall-like weather is expected starting Friday, with sunny skies and light winds persisting into early next week. && .DISCUSSION... The center of the low pressure system is making its way down the coast and headed for SoCal tonight. As it brushes by northern Nevada, we`re seeing an area of frontogenesis/deformation set up south of I-80. Rain showers are currently ongoing at the time of this writing from Storey County down to Mono County, but are expected to fizzle out by daybreak. Very low chances of around 10% for lightning are expected out of these showers as well. Through this morning we`ll have a few showers (20-30%) that linger over Mono and Mineral counties. As we get into this afternoon, hi-res models have another round of scattered thunderstorms mostly south of I-80, although a few showers may pop up around Pyramid Lake. Current chances are 20-50% across western Nevada and 70-80% from Lake Tahoe south along the Sierra. With these afternoon showers, we`ll likely see some degree of lightning activity, as current chances are 20-30%. Snow will be back in the forecast today, but only a dusting up to 2" above 9500`. Tioga Pass will likely see some snowflakes falling again, but only half of an inch is expected in the morning before the snow switches over to rain around 10am-12pm. With that low moving further south throughout this afternoon and instability diminishing after sunset, we can expect all showers to be done by 11pm tonight. After today, the weather really quiets down. Temperatures start to level off around 80 in lower valleys and 70`s in the Sierra. Winds will be relatively light each afternoon through the weekend and into early next week. There`s what looks to be a possible Rex Block setting up just off the West Coast the first half of next week. High pressure will be working in our favor at first, then as the Block breaks down, a shortwave trough brushes by northern Nevada on Wednesday. Not a huge concern as of right now other than the potential for gusty winds, but something we`ll monitor as we get closer to Wednesday. -Justin && .AVIATION... Ongoing dense fog at KTRK that will likely disperse between 13-15Z this morning. There are also some rain showers over KRNO/KCXP/KMEV that will pass by 11-12Z this morning. Expect just a few more hundredths of an inch of precip this morning from these showers. A 30-50% chance of showers and a 20-30% chance of lightning are expected this afternoon from KRNO down to KHTH, including KTRK and KTVL. KMMH will have a greater chance of seeing thunderstorms at 70%. The best timing of the showers will be from 20Z-05Z. FL100 and sfc winds will be relatively light throughout today, although we can`t rule out some light turbulence. With the exception of brief gusts up to 25 kt near t-storms, light winds will prevail through the remainder of the week. VFR conditions will prevail from Friday onward as well, with the exception of fog returning to KTRK tomorrow morning. -Justin && .REV Watches/Warnings/Advisories... NV...None. CA...Winter Weather Advisory until 8 PM PDT this evening CAZ073. && $$