Heavy Rain and Thunderstorms in the Plains; Tropical Moisture Brings Heavy Rain to Southern California and Southwest

Heavy rain showers and thunderstorms, some severe, will persist across the Plains and Mississippi Valley through Friday. Increasing tropical moisture from the remnants of Mario will bring showers, thunderstorms, and a flash flooding threat across much of southern California into the Desert Southwest through Friday. Read More >

Hot Temperatures and/or High Heat Index Values

Heat Safety Information
The State College NWS Office will issue Advisories and Warnings under the header "PHLNPWCTP (WWUS71 KCTP)" for the following:
Extreme Heat Warning: Heat Index values will attain or exceed 105°F. Extreme Heat Watch: Possibility that Extreme Heat Warning Criteria may be met at longer ranges (12 to 48 hrs out).	Map of Extreme Heat Warning Criteria
Heat Advisory: Heat Index will be equal to or greater than 100°F, but less than 105°F.	Map of Heat Advisory Threshold
For an outlook beyond 3-4 days, see the extended heat index guidance we get from the NWS's Weather Prediction Center (WPC): Maximum Heat Index Outlooks

Cold Temperatures and/or Low Wind Chill Values

Cold Weather Safety Information
The State College NWS Office will issue Advisories and Warnings under the header "PHLNPWCTP (WWUS71 KCTP)" for the following:
Either wind chill or temperatures can meet these criteria (i.e. if there is light/no wind, temperatures alone can trigger these products)
Extreme Cold Warning Values of -20 F or colder along and south of I-80, and -25 F or colder for areas north of I-80	Extreme Cold Warning Map
Cold Weather Advisory Values of -10 F or colder along and south of I-80, and -15 F or colder for areas north of I-80	Cold Weather Advisory Map