textproduct: Reno

KEY MESSAGES

* Strong high pressure will result in historic March warmth this week.

* The warm temperatures will accelerate snowmelt, leading to rivers running fast and cold.

* Dry and mild weather is favored through the weekend, but a pattern change is possible by March 24th or 25th.

DISCUSSION

The heat is on it's way, as a strengthening ridge of high pressure draws nearer. The center of the ridge circulation will migrate overhead of the southwestern region starting Tuesday, which will signal the beginning of 80s in western Nevada valleys and 70s for Sierra communities. By the end of the week, upper 80s are expected for western Nevada, with lower valleys across the Basin and Range flirting with low 90s. Upper 70s to low 80s will be found in Sierra valleys along US-395 in Alpine and Mono counties for Thursday and Friday. We are anticipating record high temperatures being challenged or set this week, before the ridge nudges eastward over the following weekend. Our chances for record breaking high temperatures is nearing 100% from Tuesday through Friday. Next weekend we will see the winds pick up along ridges as temperatures hold around 15 degrees above seasonal averages.

Our main impacts from this strong warming will be a continued reduction in snowpack across the Sierra, which will keep local rivers and streams running cold and fast. While it might be tempting in this heat to cool off in the rushing waters, we advise steering clear of area rivers and streams. The water will be cold enough to induce shock, and fast enough to overwhelm even a strong swimmer, so staying away from river banks is advised to keep safe. While the rivers and streams will be running high, no flooding is expected at this time.

Once the ridge moves on next weekend, our chances for windy or wet weather shifts closer to the region into next week. Temperatures are looking to stay above average (~10 degrees above average), so we don't expect much in the way of wintry conditions returning any time soon. HRICH

AVIATION

* Light winds and VFR conditions today through the week. Strong warming will bring density altitude concerns to the region. Inversions in valleys will bring reductions to slantwise visibility due to haze building over this week. HRICH

CLIMATE

Both area climate sites (Reno at KRNO and South Lake Tahoe at KTVL) have potential to see multiple records broken going through this weekend.

Current record high temperatures for mid-March:

Date Reno,NV South Lake Tahoe,CA ---- ------------ ------------------- 3/17 78F in 2007 65F in 2007 3/18 77F in 1947 63F in 2004 3/19 77F in 1997 65F in 2015 3/20 81F in 2004 68F in 1997 3/21 80F in 2004 68F in 1997 3/22 77F in 2004 65F in 2004

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Current record warmest low temperatures for mid-March:

Date Reno,NV South Lake Tahoe,CA ---- ------------ ------------------- 3/17 48F in 2015 38F in 2007 3/18 47F in 1945 37F in 2021 3/19 46F in 2013 38F in 2013 3/20 47F in 2013 35F in 2013 3/21 46F in 2015 38F in 1972 3/22 50F in 2012 40F in 2012

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Normal high temperatures for mid-March:

Date Reno,NV South Lake Tahoe,CA ---- ---------- ------------------- 3/17 60F 48F 3/18 60F 48F 3/19 60F 48F 3/20 60F 49F 3/21 60F 49F 3/22 61F 49F

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Warmest daily March temperatures on record:

Reno, NV: 83F on 3/31/1966

South Lake Tahoe, CA: 71F on 3/30/2015

REV Watches/Warnings/Advisories

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