Weather Alerts for California
1. Air Quality Alert for: Imperial Valley
2. Freeze Warning for: Northeast Siskiyou and Northwest Modoc Counties; Modoc County; Klamath Basin; Northern and Eastern Klamath County and Western Lake County; Central and Eastern Lake County
3. Red Flag Warning for: Northern Sacramento Valley to Southern Tehama County Line Below 1000 Ft; Central Sacramento Valley including Glenn/Colusa/Yuba/Northern Sutter/Butte County Below 1000 Ft; Southern Sacramento Valley In Yolo/Sacramento/Far Western Placer/Southern Sutter and Solano County Below 1000 Ft - Excludes the Delta; Eastern Delta; Northern San Joaquin Valley in San Joaquin and Stanislaus Counties Below 1000 ft - Excludes the Delta; Southeast Edge Shasta/Trinity NF and Western Portions of Tehama/Glenn RU; Northern Sierra Foothills from 1000 to 3000 Ft. Includes Nevada-Yuba-Placer RU and Anador-Eldorado RU; Eastern Mendocino NF
4. Red Flag Warning for: Southern Ventura County Mountains; Northern Ventura County Mountains; Interstate 5 Corridor
5. Red Flag Warning for: West Side Hills; San Joaquin Valley; Tehachapi Area; Fort Tejon
6. Red Flag Warning for: Western San Gabriel Mountains and Highway 14 Corridor
7. Wind Advisory for: Interstate 5 Corridor; Western Antelope Valley Foothills
8. Wind Advisory for: Santa Barbara County Southwestern Coast; Santa Ynez Mountains Western Range
9. Wind Advisory for: Santa Clarita Valley
10. Wind Advisory for: Santa Ynez Mountains Eastern Range
11. Wind Advisory for: Western San Gabriel Mountains and Highway 14 Corridor
Want more detail? Get the Complete 7 Day and Night Detailed Forecast!
Current U.S. National Radar--Current
The Current National Weather Radar is shown below with a UTC Time (subtract 5 hours from UTC to get Eastern Time).
![Current National Radar Current U.S. National Radar](https://radar.weather.gov/Conus/Loop/NatLoop_Small.gif)
National Weather Forecast--Current
The Current National Weather Forecast and National Weather Map are shown below.
![Today's National Weather Map Today's National Weather Map](https://www.wpc.ncep.noaa.gov/noaa/noaad1.gif)
National Weather Forecast for Tomorrow
Tomorrow National Weather Forecast and Tomorrow National Weather Map are show below.
![Tomorrows National Weather Map Tomorrows National Weather Map](https://www.wpc.ncep.noaa.gov/noaa/noaad2.gif)
North America Water Vapor (Moisture)
This map shows recent moisture content over North America. Bright and colored areas show high moisture (ie, clouds); brown indicates very little moisture present; black indicates no moisture.
![Water Vapor Map North American Water Vapor Map](https://www.ssd.noaa.gov/PS/PCPN/DATA/RT/NA/WV/20.jpg)
Weather Topic: What is Rain?
Home - Education - Precipitation - Rain
Next Topic: Shelf Clouds
Precipitation in the form of water droplets is called rain.
Rain generally has a tendency to fall with less intensity over a greater period
of time, and when rainfall is more severe it is usually less sustained.
Rain is the most common form of precipitation and happens with greater frequency
depending on the season and regional influences. Cities have been shown to have
an observable effect on rainfall, due to an effect called the urban heat island.
Compared to upwind, monthly rainfall between twenty and forty miles downwind of
cities is 30% greater.
Next Topic: Shelf Clouds
Weather Topic: What is Sleet?
Home - Education - Precipitation - Sleet
Next Topic: Snow
Sleet is a form of precipitation in which small ice pellets are the primary
components. These ice pellets are smaller and more translucent than hailstones,
and harder than graupel. Sleet is caused by specific atmospheric conditions and
therefore typically doesn't last for extended periods of time.
The condition which leads to sleet formation requires a warmer body of air to be
wedged in between two sub-freezing bodies of air. When snow falls through a warmer
layer of air it melts, and as it falls through the next sub-freezing body of air
it freezes again, forming ice pellets known as sleet. In some cases, water
droplets don't have time to freeze before reaching the surface and the result is
freezing rain.
Next Topic: Snow