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.
|July 14 2016|
|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|
|MONSOONAL MOISTURE WATCH FOR SUNDAY
SYNOPSIS FROM THE SAN DIEGO OFFICE
Fair weather will continue into the weekend with coastal low clouds and patchy fog during the nights and mornings with sunshine during the afternoon. Locally gusty winds will occur in the mountains and deserts as a trough digs into the area this weekend. Ridging will re-build into Southern California next week. No rain is forecast through the period, though monsoonal moisture moving into Arizona will be watched for possible intrusion into the area sometime next week
Next week`s weather looks benign west of the mountains with gradual warming as ridging re-builds into SoCal. High confidence there. However, lower confidence for the mountains/deserts as we will have to watch the progression of monsoonal moisture which will enter Arizona. Depending on the trough/ridge placement pattern next week, some of the moisture could pull far enough west into the area to lead to the potential of isolated thunderstorms from the deserts to the mountains. However, kept a dry forecast for now, due to low confidence and the global model consensus towards a drier scenario
SYNOPSIS FROM THE PHOENIX OFFICE
A warm and very dry airmass will remain in place across the Desert Southwest this entire week continuing the significant break in the monsoon. Afternoon temperatures will generally run a few degrees above normal. A return of monsoon moisture will gradually bring chances for thunderstorms, possibly as early as Sunday over high terrain areas and then the lower deserts sometime early next week
Starting on Sunday, there are continued signs of a change in the pattern which will allow for a gradual return of moisture from the east into the lower deserts and a slowly increasing threat for afternoon and evening monsoon convection. On Sunday, upper troffing strengthens along the Pacific northwest coast and in response the upper ridge builds to the north over the west central CONUS. This allows steering flow to turn to the south/southeast across south central Arizona, opening the door for moisture to spread into the higher terrain areas first - and then the lower deserts. On Sunday we will have a slight chance of afternoon/evening storms in southern Gila county along with increasing mid/high clouds that will spread west and into the lower deserts west of Phoenix. Unfortunately it does not appear that moisture will be deep enough to make much of a dent in the high temperatures, and we will call for yet another 110 degree day in Phoenix on Sunday.
For the first half of next week, Monday into Wednesday, both the GFS and ECMWF continue to build the ridge towards the north, turning steering flow more and more to the east/southeast across the lower deserts of Arizona, allowing monsoon moisture to work westwards and into the lower deserts west of Phoenix all the out to the lower Colorado River valley. As this occurs we will see an increasing threat for thunderstorms and our POPs reflect this trend.
|Weather Story Phoenix Station||Weather Story San Diego Station|