textproduct: Reno

KEY MESSAGES

* Warmth continues with afternoon temperatures remaining near 20 degrees above seasonal averages through midweek, with daily records being challenged.

* Afternoon breezes will increase through Wednesday, with choppy lake waters and travel impacts possible.

* Dry and warm conditions will continue through at least the end of March with a potential shift toward a cooler and wetter weather pattern.

DISCUSSION

The continued heat is currently being driven by an unusually robust upper-level ridge and attendant surface high pressure, with upper air analysis revealing 500 hPa height anomalies over Reno reaching a staggering +200 to +225 meters above normal. Afternoon highs through Wednesday will stay approximately 20 degrees above seasonal norms, reaching the low-to-mid 80s for western Nevada valleys and the upper 60s to low 70s for Sierra valleys. A widespread swath of cirrus and lenticulars may provide some intermittent shading today, which could cool afternoon highs a few degrees.

Lower-level mixing will facilitate momentum transfer aloft to the surface as zonal flow strengthens across the region through midweek. Latest high-resolution model guidance shows 700 hPa winds peaking between 45-55 kts today over the Sierra crest, which is stronger than previous projections. While todays thicker cloud cover may initially inhibit full vertical mixing into the valleys, west to southwest wind gusts up to 25-30 mph are possible today. Surface pressure gradients will strengthen Tuesday and Wednesday as skies clear, with southwest wind gusts persisting 25-35 mph on Tuesday. This gradient will be at its tightest on Wednesday as a shortwave trough passing through the Pacific Northwest drags a dry cold front into northwest Nevada, producing southwest winds of 10 to 25 mph and widespread gusts of 30-40 mph that will lead to choppy conditions on area lakes and potential aviation turbulence.

A temporary 10-15 degree cooling trend will arrive on Thursday behind the dry cold front, though ridging is expected to rebuild quickly for another warm-up through the final weekend of March. Looking toward the start of April, ensemble guidance suggests a potential shift toward a cooler and wetter pattern, though confidence in the timing and position of storms remains low.

-Johnston

AVIATION

Flight conditions will remain solidly VFR areawide over at least the next week. Expect a steady stream of high-altitude cirrus, with mountain wave development becoming increasingly prominent through the remainder of the day.

Aloft at FL100, west-southwest winds will peak 45-55kt today, settling slightly into the 35-45 kt range Tuesday and Wednesday. This set up will drive mountain wave turbulence and localized LLWS in the lee of the Sierra, specifically during the peak mixing window of 18-03Z.

Surface winds will increase each afternoon today through Wednesday, with gusts of 25-30kt as these FL100 winds mix to the surface.

-Johnston

CLIMATE

The heat hits keep on coming for both Reno and South Lake Tahoe. While the monthly records set last week won't be challenged this week, more daily record highs are within reach at both sites today through Wednesday, and also by the final weekend of March.

* New March monthly record high at Reno:

- Reno, NV: New record of 88F on Friday March 20. The previous monthly record was 86F on 3/18/2026.

* New March monthly record high at South Lake Tahoe:

- South Lake Tahoe, CA: New record of 76F on Wednesday March 18. The previous monthly record was 71F on 3/30/2015.

New daily record high temperatures and the previous daily record high temperatures for Reno and South Lake Tahoe:

Date Reno NV South Lake Tahoe CA ---- ------------ ------------------- 3/17 82F (old 78F in 2007) 69F (old 65F in 2007) 3/18 86F (old 77F in 1947) 76F (old 63F in 2004) 3/19 85F (old 77F in 1997) 72F (old 65F in 2015) 3/20 88F (old 81F in 2004) 72F (old 68F in 1997) 3/21 81F (old 80F in 2004) 70F (old 68F in 1997) 3/22 77F (tied with 2004)69F (old 65F in 2004) 3/23 77F - 202266F - 2022 3/24 80F - 202265F - 2022 3/25 81F - 202267F - 2022 -------------------------------------------------------

New daily record warmest low temperatures and the previous daily record warmest low temperatures for Reno and South Lake Tahoe:

Date Reno NV South Lake Tahoe CA ---- ------------ ------------------- 3/18 48F - 1904 37F - 2021 3/19 46F - 2013 38F - 2013 3/20 47F - 2013 35F - 2013 3/21 50F (old 46F in 2015) 38F - 1972 3/22 50F - 201240F - 2012 3/23 46F - 200040F - 1998 3/24 45F - 200640F - 1986 3/25 52F - 189338F - 2008

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REV Watches/Warnings/Advisories

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