National Weather Service United States Department of Commerce

Another Round of Heavy Rain and Mountain Snow in California; Snow in the Great Lakes and Northeast

Another round of heavy rainfall will renew concerns for additional flash flooding and landslides in southern California around burn scars and coastal mountain ranges. A low pressure system is bringing enhanced snowfall downwind from the lower Great Lakes into the Northeast mountain ranges. Above average temperatures will challenge or break daily record high temperatures across the southern Plains. Read More >

12-hour helicity forecast

 

Figure 7: ETA 12 Hour Forecast of 250-850 mb Qn vectors,
thickness and isotachs valid 1200 UTC May 12, 1997.

 

18-hour helicity forecast

 

Figure 8: ETA 18 Hour Forecast of 250-850 mb Qn vectors,
thickness and isotachs valid 1800 UTC May 12, 1997.