221
FXUS66 KSTO 042040
AFDSTO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
140 PM PDT SUN MAY 4 2025
FOR ADDITIONAL DETAILS ON WEATHER AND EXPECTED IMPACTS OVER THE
NEXT 7 DAYS, PLEASE VISIT WEATHER.GOV/STO/BRIEFING.
DISCUSSION
SYNOPSIS
A WEAK WEATHER SYSTEM WILL CONTINUE TO BRING ISOLATED LIGHT
SHOWERS AND THUNDERSTORMS OVER THE SIERRA AND FOOTHILLS TODAY,
MAINLY SOUTH OF I-80. BREEZY TO GUSTY NORTH TO EAST WINDS ARE
EXPECTED THROUGH EARLY TUESDAY MORNING. DRY AND WARM WEATHER
RETURNS THIS WEEK WITH ABOVE NORMAL TEMPERATURES. POTENTIAL FOR
MODERATE HEATRISK LATE WEEK ACROSS PORTIONS OF THE NORTHERN AND
CENTRAL SACRAMENTO VALLEY.
KEY MESSAGES
* TODAY-MONDAY:
-ISOLATED SHOWER AND THUNDERSTORMS OVER THE SIERRA AND FOOTHILLS
THROUGH THROUGH EARLY THIS EVENING AS THE SYSTEM EXITS THE
REGION (10-30% PROBABILITY, BEST CHANCES SOUTH OF INTERSTATE
80).
-GUSTY NORTH TO EAST WINDS ARE EXPECTED THROUGH MONDAY, STRONGEST
ALONG AND WEST OF INTERSTATE 5. A WIND ADVISORY REMAINS IN
EFFECT FOR THE SACRAMENTO VALLEY AND DELTA UNTIL 8 PM MONDAY.
65-95% PROBABILITY OF GUSTS OVER 40 MPH IN THE SACRAMENTO VALLEY
AND DELTA AREAS.
* TUESDAY - LATE WEEK:
-BREEZY NORTH TO EAST WINDS WILL LINGER INTO EARLY TUESDAY MORNING.
OTHERWISE, PERIODICALLY BREEZY ONSHORE WINDS.
-DRY AND WARM WEATHER WITH ABOVE NORMAL TEMPERATURES UNDER UPPER LEVEL
RIDGING.
-MODERATE HEATRISK POSSIBLE ACROSS THE NORTHERN AND CENTRAL
SACRAMENTO VALLEY FRIDAY-SATURDAY. PROBABILITY OF HIGH
TEMPERATURES 90 DEGREES F OR HIGHER: 50-90% ACROSS THE CENTRAL
VALLEY FRIDAY-SATURDAY.
CHANGES FROM PREVIOUS FORECAST
-BREEZY NORTH TO EAST WINDS WILL LINGER INTO EARLY TUESDAY
MORNING.
-MODERATE HEATRISK POSSIBLE ACROSS THE NORTHERN AND CENTRAL
SACRAMENTO VALLEY FRIDAY AND SATURDAY.
AVIATION
VFR CONDITIONS OVER INTERIOR NORCAL NEXT 24 HOURS. GUSTY NORTH
SURFACE WINDS OF 30-45 KNOTS IN THE VALLEY AND DELTA, STRONGEST IN
THE WESTERN SACRAMENTO VALLEY AND NORTHERN SACRAMENTO VALLEY.
35-45 KNOTS OVER THE MOUNTAINS, ALONG WITH A 15-30% CHANCE OF
ISOLATED THUNDERSTORM DEVELOPMENT OVER THE SIERRA MAINLY FROM I-80
SOUTHWARD UNTIL AROUND 04Z MONDAY.
STO WATCHES/WARNINGS/ADVISORIES
WIND ADVISORY UNTIL 8 PM PDT MONDAY FOR CARQUINEZ STRAIT AND
DELTA-CENTRAL SACRAMENTO VALLEY-NORTHERN SACRAMENTO VALLEY-
SOUTHERN SACRAMENTO VALLEY.
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