FXUS66 KSTO 192010

AFDSTO



Area Forecast Discussion

National Weather Service Sacramento CA

110 PM PDT Thu Mar 19 2026





.KEY MESSAGES...



 - Record breaking heat continues today & Friday, with widespread

   Minor HeatRisk and areas of Moderate HeatRisk.



 - Slightly cooler temperatures this weekend and into next week,

   but temperatures will be 15-20 degrees above-normal.



&&



.DISCUSSION...



...Today-Friday... 

Strong high pressure continues to dominate the synoptic pattern 

this week, resulting in record-breaking heat across much of the 

area. Yesterday, Sacramento, Modesto, and Stockton recorded/tied 

their all-time hottest March day on record; and Modesto AP 

recorded it's earliest 90 degree day on record. Today and Friday 

will see the hottest temperatures of the week, with widespread 

Minor HeatRisk and areas of Moderate HeatRisk. The NBM is 

currently forecasting a 70-90% chance of highs 90 or greater 

throughout the Valley and Delta today & Friday. If Stockton AP or 

Sacramento hits 90 degrees today, it will be the earliest 90 

degree day on record at those two sites.



...Saturday-Wednesday... 

Temperatures cool down slightly over the weekend, as ridging 

flattens out and shifts eastward over the Great Basin. 

Temperatures will still be several degrees above-normal, but are 

forecast to be slightly cooler than previous days. Minor HeatRisk 

will still be widespread especially in the Valley and Delta, but 

some areas in the mountains will fall below any HeatRisk concerns.



There is still a degree of uncertainty regarding the eastward 

trajectory of the high, which could allow a weak lobe of energy 

to bring very light showers over the Shasta County mountains mid 

next week. However, probabilities for 0.1" or more are currently 

less than 25%. The majority of ensembles favor the redevelopment 

of high pressure and rising heights mid next week, which would 

yield continued dry weather and above-normal temperatures.



If you are outside or planning outdoor activities this week and

over the weekend, please remember to drink plenty of water and 

wear sunscreen. As this is an anomalous heat event, individuals 

may not be fully acclimated to the emerging heat. Local waterways 

are also running very cold due to snowmelt.







&&





.AVIATION...

VFR conditions are expected for the next 24 hours. Surface winds 

below 12 kts and generally from the north. Chances (20-45%) of 

lower visibilities tomorrow morning, mainly Sacramento southward 

from BR conditions reducing visibility to MVFR conditions. Best 

chances from around 11z through 15z Friday. &&



.STO WATCHES/WARNINGS/ADVISORIES...

None.

&&



$$