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.
|April 29 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|
|BRIEF DISCUSSION FROM THE PHOENIX OFFICE
Cool upper low continued to transition off towards the Northeast this morning with the main low center East/Northeast of the four corners area as seen in vapor imagery and morning plot data. 12Z 500MB plots indicated cyclonic shear/curvature to the flow over Eastern Arizona helping support weak upward motion and with a wrap around deck of mid level moisture present from the greater Phoenix area Eastward. The UVV led to some thick cloud decks with bases 8-10K feet and light showers emanating from some of them. As such slight chances for light showers remains in the forecast from Phoenix Eastward this morning into the afternoon hours.
SYNOPSIS FROM THE PHOENIX OFFICE
Dry Northwest flow aloft will increase over the region today through Saturday. Warmer afternoon temperatures are also forecast. However, another Pacific low pressure system is expected to move into the region Saturday night and Sunday developing breezy conditions and a threat for showers and thunderstorms. The best chance of precipitation will occur over the South Central Arizona deserts and mountains mainly in the vicinity of Phoenix. Clearing is expected Sunday night with high pressure and much warmer weather next week.
BRIEF DISCUSSION FROM THE SAN DIEGO OFFICE
A deep marine layer is in place this morning with visible satellite indicating patchy stratus over the coast and valleys with mostly widespread stratus over the coastal waters. The 12Z Miramar sounding shows a marine layer inversion at around 3000 feet with Northwest flow aloft. Water vapor satellite shows a trough over the inter-mountain West a ridge to our West allowing for the aforementioned Northwest flow aloft over Southern California. Hi-res models indicate that stratus should at least partially clear out today and higher 500mb heights moving in and significantly less cloud cover should result in highs several degrees higher than yesterday
SYNOPSIS FROM THE SAN DIEGO OFFICE
Dry and a little warmer today under weak high pressure. A low pressure system moving Southward through the Western states will bring cooling and gusty winds for the mountains and deserts Saturday with a chance of showers and slight chance of thunderstorms for Saturday afternoon and evening. Dry and warmer for Sunday through Tuesday with high pressure aloft off the west coast although a weak disturbance could create some shower and thunderstorm activity over the mountains and high deserts Sunday afternoon and evening. For Wednesday through Friday cooling will spread inland with increasing clouds toward the end of the week as a low pressure system over the eastern Pacific moves slowly towards the West coast. Some precipitation could occur by Friday.
|Weather Story Phoenix Station||Weather Story San Diego Station|