textproduct: Elko

KEY MESSAGES

* Moderate to major risk for heat-related illnesses for most of Northern and Central Nevada today

* A few strong thunderstorms possible in parts of Northern and Central Nevada through this evening

* Monsoon weather pattern for Central and Eastern Nevada expected to continue through the next week

* Slow cooling trend expected Monday through Friday

DISCUSSION

(This afternoon through next Sunday)

WEATHER PATTERN OVERVIEW: Current radar loop is showing a fairly active period. Convective activity began late this morning across portions of US Highway 50 and also over portions of Elko county and northern White Pine county. Storm motion with the cells across the central portion of the forecast area are clocking in at 5 to 10 knots. The cells in central Nevada are of the mix wet/dry variety but will transition to mostly wet by later this afternoon and evening. The cells further north are expected to be more on the dry side due to a warmer air mass. The main threats from these storms are cloud to ground lightning strikes possibly creating new fire starts, brief moderate rainfall, and wind gusts to 55 mph. In addition to the above threats, the heat headlines will also continue for all the area through 11pm tonight. The exception is zone 033, where the extreme heat warning will continue until 11pm Monday evening. Overnight lows will be in the 50s and 60s.

The large upper level ridge over the four corners region will continue to remain in its location for the next day or two. This will keep a fairly weak southerly to southwesterly flow aloft across the forecast area. Models are hinting at a weak upper level trough developing along the western coast of the United States. A weak southwest flow is expected that will shunt some of the subtropical moisture east, especially over northern Nevada. This will bring a decrease in the convective activity across the north, though activity is expected to continue in central Nevada as evident by the decreasing precipitable water values in the north. Highs in the north will be a degree or three cooler with readings in the low to upper 90s expected over the area. Winds will be breezy especially over the north with gusts 25 to 30 mph. Isolated to scattered showers and isolated thunderstorms are expected mainly across the US Highway 50 corridor with some activity reaching southern Elko county. Main threats will be the cloud to ground lightning strikes and wind gusts to 50 mph. Look for activity to gradually wane during the overnight hours with lows in the 50s and 60s.

By Tuesday, all models show the slow strengthening of the upper trough across the western United States with the four corners ridge maintaining its position. Convective activity will again be confined to those locales along the US Highway 50 corridor. Afternoon high temperatures are expected to again cool by several degrees with readings in the low to mid 90s. Winds will be breezy during the afternoon with gusts of 20 to 25 mph. Overnight lows will be in the 50s.

On Wednesday, a weak disturbance is expected to push across northern and central Nevada during afternoon and evening. This looks like it will lead to an uptick in the convective activity as guidance is showing a fifty to seventy percent chance of showers and thunderstorms during this time frame. WPC is highlighting this time with an area expansion northward of the excessive rainfall outlook. Will need to continue looking at this event as it unfolds for moderate to locally brief heavy rainfall. Storm motions at this time are forecast to be around seven to 14 knots. Highs in the afternoon will further cool with readings in the 80s and 90s. Shower activity will continue into the overnight with lows in the 50s.

Thursday through Sunday, models continue to show a daily pattern of shower and thunderstorm activity with high temperatures continuing to cool. Readings are expected to drop into the 80s by next weekend with lows in the 50s.

FORECAST CONFIDENCE & DEVIATIONS:

Near term forecast modifications were required to the PoP, weather, wind speed, and wind gust grids to account for fire weather and storm development in the northeastern parts of the forecast area while bumping up PoP chances in central Nevada. In the short term, similar changes were made to the aforementioned elements. Confidence remains high on a cooling trend as afternoon and evening thunderstorms continue in central Nevada with slightly cooler air in the north. Confidence is currently moderate for Wednesday's convective development.

AVIATION

VFR conditions are expected to continue across all terminals over the next 24 hour period. VCTS chances remain this evening at KELY, KEKO, and KENV. Strong gusty convective wind gust of 45KT can be expected from nearby thunderstorms, especially at the above listed terminals. Convection expected again tomorrow with VCTS at KELY with gusts to 20-25KT across the northern terminals KWMC-KBAM- KEKO-KENV.

FIRE WEATHER

Elevated fire weather conditions will continue across portions of northern Nevada this afternoon and tomorrow due to west wind gusts near 25 mph and minimum relative humidity values as low as seven percent. Current radar is depicting scattered showers and isolated to scattered thunderstorms in central Nevada (storms appearing more on the wet side), mainly across fire zones 425 and 427, with storms more isolated and slightly drier in nature across 469 and 470. Storm coverage is expected to be confined in the central zones tomorrow, including the southern portions of 470) and Tuesday, with a distinct ramping up of convection for Wednesday as southerly flow continues to push moisture north.

LKN Watches/Warnings/Advisories

Heat Advisory until 11 PM PDT this evening for NVZ031-034-035

Excessive Heat Warning until 11 PM PDT Sunday NVZ030-036>041

Excessive Heat Warning until 11 PM PDT Monday NVZ033