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.
|October 25 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|
|SYNOPSIS FROM THE SAN DIEGO OFFICE
High pressure aloft is beginning to weaken as are the Santa Ana winds. The heat peaked for coastal and western valley areas on Tuesday but high temperatures will still be well above average today with some inland coastal and western valley areas exceeding 100. The flow will turn weakly onshore flow Thursday through the weekend with slow cooling spreading inland. A weak trough of low pressure near California early next week could bring greater cooling and a return of night and morning coastal low clouds and fog. High pressure aloft is weakening and the Santa Ana winds are weakening as well. The winds are more localized than 24 hours ago with strongest gusts to around 40 mph. Locally gusty winds will continue into this morning then diminish during the afternoon. Even though winds aren`t necessarily surfacing in as many areas there is still enough wind aloft and mixing to keep temperatures warmer especially near the coastal foothills though the warmer locations early this morning exceed 80 versus 90 yesterday morning. It will not be quite as hot for coastal and western valley areas today but high temperatures will still be well above average with temperatures exceeding 100. Weak onshore flow will return on Thursday with slow cooling spreading inland through the weekend. For early next week a weak trough of low pressure may develop in the vicinity of California but with continuing run to run and model to model differences across the eastern Pacific into the West Coast. A weak trough of low pressure near California would bring greater cooling and a return of night and morning coastal low clouds and fog.
SYNOPSIS FROM THE PHOENIX OFFICE
High pressure will slowly weaken through the remainder of the week resulting in a gradual cooling trend, though temperatures will continue to remain above normal. Afternoon highs in the lower and middle 90s will be common for lower elevation communities into the weekend. Dry conditions will also persist with no chance of rain through the end of the month. One more day of near-record warmth (at least across South-Central AZ) as the very strong ridging that has been over the region the past few days begins to weaken/flatten as a strong shortwave digs southward into the northern Rockies. Model forecast 500mb temps in the -8C to -9C range this afternoon are at near-record values for this time of year, but it is around 2 degrees C than what we saw yesterday. These warm temperature aloft will be good enough to support mid-90s across most of the lower desert locations, with a few upper 90s across SE CA, which could threaten a few records across South-Central AZ today, under mainly clear skies.
|Weather Story Phoenix Station||Weather Story San Diego Station|