Old Advisory Events
The information herein is NOT intended for use as a weather forecast. The Air District DOES NOT forecast but solely compiles information from both the Phoenix and San Diego National Weather Offices to relay information concerning potential changes in ambient air concentrations that may impact the public.
|September 7 2017|
|High wind levels have the potential to suspend particulate matter into the air. High levels of PM10 may pose an impact to public health. It is recommended that active children and adults, and people with respiratory disease, such as asthma, limit their outdoor activities.
Potential increases in PM10 concentrations may increase to moderate or unhealthy level.
|Imperial County Weather Synopsis|
|BLOWING DUST POSSIBLE LATE THIS AFTERNOON AND EVENING.
DUST STORM WARNING HAS BEEN ISSUED BY THE NWS PHOENIX OFFICE FOR THE SOUTHERN PORTION OF IMPERIAL COUNTY. NOTICE IS IN EFFECT UNTIL 6PM THIS EVENING.
The National Weather Service in Phoenix has issued a Dust Storm Warning, which is in effect until 6 PM PDT this evening. Affected area is the southern portion of Imperial County including the communities of El Centro and Imperial as well as Interstate8. Effective through 6 pm this evening. Gusty winds south to southwest winds 20 to 40 mph. Areas of visibility 1 to 3 miles with local visibility down to near zero. Sharply reduced visibility leading to extremely hazardous driving conditions.
FLASH FLOOD WATCH IN EFFECT FOR PORITIONS OF SW ARIZONA AND SE CALIFORNIA.
The National Weather Service in Phoenix has issued a Flash Flood Watch for portions of southwest Arizona and southeast California. Affected areas include Imperial County and portions of Joshua Tree National Park, the Chiriaco Summit, Blythe, and Palo Verde, effective through Saturday evening.
Additionally, the San Diego NWS office reports thunderstorms are now Developing over portions of San Diego County. At 1:42 pm radar image shows thunderstorms developing over the San Diego county mountains. As the day progresses, expect isolated thunderstorms over the mountains and into the Sand Diego County deserts.
SYNOPSIS FROM THE SAN DIEGO OFFICE
Decreasing moisture and instability today will result in lower chances for mountain and desert thunderstorms. Cooler through Saturday with a cut-off low forming off the West Coast. The low will bring increasing moisture Friday through Sunday, with better chances for afternoon and early evening thunderstorms in the mountains and deserts. Some storms may move west of the mountains Sunday. Warmer Monday and Tuesday with higher pressure aloft. A closed low will form off the central CA coast during the day Friday, before digging south and becoming cut off Saturday and Sunday. Circulation around this low will pull up more subtropical moisture from the south for better chances of showers and thunderstorms over the mountains and deserts and minor cooling
Friday and Saturday. As the low drifts further southwest late Saturday, moisture is forecast to wrap around the north side of the low into the high deserts. Increasing moisture and elevated instability coupled with lift associated with a jet streak pushing into So Cal will create the potential for nocturnal thunderstorms early Sunday morning, mainly over the mountains and deserts.
SYNOPSIS FROM THE PHOENIX OFFICE
Increasing southerly flow aloft ahead of a upper-level low center approaching will increase moisture levels, and chances for showers and thunderstorms across the region through the upcoming weekend. Friday will likely be the most active day, with scattered to numerous showers. Very strong winds and locally heavy rains are possible with the strongest storms. Drier conditions and a warming trend will then return during the early and middle parts of next week as strong high pressure builds back over the area. Saturday and Sunday will likely see a shift westward in the area of most active weather, as the axis of best moisture/Bulk Shear shifts westward along with the main upper-level low center off the southern CA coast. There will still be a risk of severe storms/localized flooding across parts of SE CA on Saturday, with Joshua Tree NP seeing the best chances for showers/storms on Sunday. Highs Saturday will likely once again struggle to reach 100F across the lower deserts, being kept down by convective activity and leftover debris clouds. Warmer temperatures are likely in Sunday as mid-level temps rise and skies clear.
|Weather Story Phoenix Station||Weather Story San Diego Station|