textproduct: Reno

KEY MESSAGES

* After a brief cooling today, late spring warmth will prevail later this week into next week, with highs climbing to around 20 degrees above mid-March normals.

* Winds edge upward this afternoon, otherwise the storm track will remain well north of CA-NV, resulting in a continued absence of rain or snow with typical westerly afternoon breezes.

* Longer range outlooks strongly favor dry and warm conditions going through at least the third week of March.

DISCUSSION

Bottom line up front: A prolonged warmup with high temperatures more typical for late May and even early June will take place later this week and peak early-mid next week. No rain or snow is on the horizon through at least the middle of next week.

However, our overall warming trend will take a small step back today as an upper trough brushes across the Pacific NW. High temperatures will still be above average for this point in March, but about 5-10 degrees cooler than Monday from US-50 northward to the OR border, and up to 5 degrees cooler south of US-50. Winds will also kick up a bit more with gusts 25-30 mph, and isolated gusts to 35 mph this afternoon due to a tighter zonal flow over northern CA/NV. These winds will produce a short period of choppy lake conditions later today, most notably for Pyramid Lake. Sierra ridge gusts will also increase to near 55 mph through this afternoon, setting the stage for a healthy dose of mountain wave clouds--great for viewing and photos, but not very pleasant to fly through.

From Wednesday through early next week, an unseasonably strong high pressure ridge off the southern CA coast will extend northward into southern CA-NV through this weekend, and then rebuild closer to the eastern Sierra/western NV by early next week. This pattern will resume the warming trend, with highs rebounding starting Wednesday and then rising into the 70s for most lower elevations and 60s for Sierra communities from Thursday through this weekend. Another weak trough passage across the Pacific NW could bring a modest cooling and a bit more wind Saturday afternoon mainly north of I-80. The warmest days are then projected for early-mid next week, with at least a 75% chance of highs 80+ degrees for western NV valleys. Record highs (ranging from 76-80 degrees in Reno between March 13-17) could be within reach as soon as Friday, with a greater than 80% chance of at least a tied record high for Monday and Tuesday. Expect a sharp increase in green vegetation across lower elevations and foothills in time for St. Patrick's Day!

Sierra communities will also see unusual warmth, with highs climbing into the 60s from Thursday-Sunday, and making a run at 70+ degrees early next week. This prolonged warmth will accelerate snowmelt, resulting in a diurnal cycle of increased river and stream flows. Please be aware of these high flows and stay away from waterways, especially beginning this weekend, as cold and fast-moving water can be dangerous. MJD

AVIATION

The main aviation-related impact for the upcoming week will be increased west winds this afternoon with gusts 20-25 kt, and approaching 30 kt for far western NV terminals. These winds will ramp up between 18-20Z and continue until 02-04Z. FL100 wind gusts near 45 kt will produce mountain wave turbulence today, with periods of LLWS especially during the late morning and midday for far western NV terminals, as the winds mix down from the ridge tops to the valleys.

Otherwise, VFR conditions will prevail for the remainder of the week, with lighter zephyr-type breezes (gusts 15-20 kt) each afternoon from Wed-Fri for western NV southward to KMMH. Winds could edge upward again Saturday afternoon.

As temperatures warm up toward mid-March, we may see minor density altitude concerns pop up for western NV terminals, especially by early next week. MJD

REV Watches/Warnings/Advisories

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