Sunrise 5:33 AM   Sunset 8:24 PM Moonrise 1:58 AM   Moonset 3:25 PM

  Print   HELP   Reset   Save   Recall  New

FXUS65 KREV 012140 AAA AFDREV

Area Forecast Discussion...UPDATED National Weather Service Reno NV 240 PM PDT Sat Jun 1 2024

SYNOPSIS

Above average temperatures and mainly dry conditions will persist through early next week with a couple of weak weather systems enhancing afternoon winds and allowing for precipitation chances later today and Monday within northern portions of the region.
Confidence is high in a significant warmup for the middle to late portions of next week as highs approach 100 degrees in the hottest western NV valleys, with afternoon thunderstorms also possible in the later half of next week.

DISCUSSION

Key Points:

* Above normal temperatures continue today along with mostly dry conditions with the exception of a 10-20% chance of isolated showers for areas north of I-80 later this afternoon.

* While dry conditions are anticipated on Sunday, the region sees more chances for isolated showers for areas north of I-80 on Monday with the entire CWA expecting 30-40 mph wind gusts possible generally out of the west.

* Triple digit (or close to it) day high temperatures are possible within the region on Wednesday through Friday along with some diurnal showers/thunderstorms in some portions on Thursday through Saturday.

Current satellite imagery shows some clouds developing in areas along and north of I-80 within the region with radar data reporting some isolated showers within Lassen County this afternoon. As the latest RAP analysis of the upper air pattern over the CWA shows a weak trough over the CWA, the 18Z HRRR forecasts some isolated light showers possible (10-20% chance) in northern Lassen, Washoe, and Pershing counties along a convergence zone where clouds are currently developing through almost 8 PM PDT. There is a chance though that this precipitation may just be virga due to drier air layer seen closer to the surface. West-northwesterly winds gusting up to around 25-30 mph are expected within the CWA through this evening before dying down overnight.

On Sunday, forecast guidance shows the upper air trough moving to the west allowing for a northwesterly upper air flow over the CWA as a weak upper air ridge trails the trough. This will allow for warm temperatures, dry conditions, and breezy afternoon winds out of the west-northwest throughout the region. For Monday, models depict another trough passing through the northwestern CONUS placing the CWA underneath its base during the afternoon hours. Enhanced zephyr breezes are expected once again at the surface on Monday as a result with winds gusting up to around 30-40 mph in the afternoon and evening hours (possible Lake Wind Advisory?). Models also show precipitation chances between 10-50% within the northern half of the CWA during the morning hours with the higher chances closer to the OR border around where a cold front sets up.
Daytime high temperatures on Monday look to cool slightly as a result ranging between the upper 60s and middle 80s.

For the remaining days of next week, ensemble guidance shows a ridge moving over the CWA on Tuesday and Wednesday before the CWA starts to take a southwesterly flow aloft on Thursday being underneath the western portion of the upper air ridge. This flow then looks to turn more southerly late Friday into Saturday as a trough moves over the Pacific Coast and pushes the ridge eastward.
At the surface, daytime high temperatures look to get hotter with portions of the CWA nearing the 90 degree mark on Tuesday. On Wednesday, the latest NBM probabilities show around an 80-95% chance of daytime highs at 90 degrees or above within western NV and a portion of adjacent CA. The coverage of these probabilities increases on Thursday while there is also around a 20-50% chance for highs to reach 100 degrees or above in some portions of western NV. NBM probabilities for daytime high temperatures of 90 degrees or higher for Friday and next Saturday look once again to be between 70-90% for western NV and portions of adjacent CA. The latest ECMWF Extreme Forecast Index (EFI) for MaxT looks to be between 0.7-0.9 on Wednesday through Friday, so this also signals the potential for above normal and hot temperatures. Please prepare now for this upcoming risk for this heat while you can! Models also show the potential for more precipitation chances towards the tail end of next week though there is still some uncertainty in coverage and probability at this time. The ECMWF EFI for CAPE shows a bulls-eye near Lake Tahoe and also down in Mono County on Friday, so these areas may be at a higher risk to see some convection. Will continue to monitor this and update the forecast as needed. -078

AVIATION

VFR conditions will prevail throughout the rest of today and into Sunday. Increased winds out of the westerly winds expected this afternoon for most TAF sites (southwesterly for KMMH), with gusts peaking around 25-30 kts between 20-06Z. Some brief light to moderate turbulence may be possible during that time as well.
Northern portions of the CWA may see a slight chance for an isolated shower or two later this afternoon and evening. -078

REV Watches/Warnings/Advisories
NV...None.
CA...None.

Sacramento #4
Click for Map
Sun -- 03:03 AM PDT     Moonrise
Sun -- 04:13 AM PDT     2.85 feet High Tide
Sun -- 05:42 AM PDT     Sunrise
Sun -- 12:28 PM PDT     0.04 feet Low Tide
Sun -- 04:29 PM PDT     Moonset
Sun -- 04:49 PM PDT     2.05 feet High Tide
Sun -- 08:25 PM PDT     Sunset
Sun -- 11:50 PM PDT     0.25 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Sacramento #4, Sacramento River, California, Tide feet

Clarksburg #4
Click for Map
Sun -- 03:04 AM PDT     Moonrise
Sun -- 03:04 AM PDT     2.85 feet High Tide
Sun -- 05:43 AM PDT     Sunrise
Sun -- 10:58 AM PDT     0.04 feet Low Tide
Sun -- 03:40 PM PDT     2.05 feet High Tide
Sun -- 04:28 PM PDT     Moonset
Sun -- 08:25 PM PDT     Sunset
Sun -- 10:20 PM PDT     0.25 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Clarksburg #4, Sacramento River, California, Tide feet

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Reno, NV,