textproduct: NWS Phoenix

KEY MESSAGES

- Near to slightly above normal temperatures will persist through the first half of the week before warming up towards the end of the week into next weekend as readings approach 110 degrees across portions of the region.

- Breezy conditions will continue through Tuesday, particularly across the Arizona higher terrain areas, resulting in elevated fire weather conditions.

- Seasonably dry conditions will persist through the next several days.

SHORT TERM /Today through Tuesday/

A broad troughing pattern remains in across the western CONUS with a shortwave progressing northeastward through southwestern Canada with another shortwave set to move in over the Pacific Northwest later today. As a result of this troughing pattern, enough of a pressure gradient remains in place across the region, and thus enhanced afternoon breeziness will remain in place through Tuesday as gusts peak at 20-25 mph, highest across the higher terrain areas to the north and east of Phoenix. The elevated gusts in combination with relative humidity values bottoming out near 10% and the very dry fuels will continue to result in elevated fire weather conditions. Under the influence of the broad troughing pattern enveloping the western CONUS, afternoon high temperatures today and Tuesday will continue to be near to slightly above normal as lower desert highs will range between 100-105F.

LONG TERM /Wednesday through Sunday/

The synoptic pattern through the middle to latter half of the week will be transitioning as the longwave trough will lift east northeastward, allowing upper-level ridging to take hold across much of the western CONUS. As a result, upper-level heights will be on the rise with the latest guidance indicating 500 mb heights increasing to near 590dm by the end of the week into next weekend. This will allow for temperatures to warm up into an above normal category, potentially as high as 5-8 degrees above normal. This means that many of the lower desert communities will be approaching 110 degrees for afternoon highs as early as Friday and continuing into the weekend.

In addition to the increasing temperatures, guidance is also showing an increase in moisture by the end of the week and the weekend as southerly mid-level flow increases. The latest EPS and GEFS show PWATs increasing as high 1.0-1.2" across much of southern AZ. This increase in moisture would certainly be enough for some isolated convection to materialize across the AZ high terrain and will be something to monitor during the next several forecast cycles.

AVIATION

Updated at 0530Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT: No major aviation weather concerns are expected during the TAF period. Winds will continue to follow diurnal tendencies with occasional afternoon gusts in upper-teens to around 20 kt. Dissipating high clouds early tonight will give way to mostly clear skies through the remainder of the period.

Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation weather concerns are expected through the next 24 hours. Winds will follow familiar diurnal trends at KIPL, while KBLH favors a S'rly component, with afternoon gusts, through Monday evening. Other than some high clouds filtering in later in the period, skies will be mostly clear.

FIRE WEATHER

Elevated fire weather conditions will persist through Tuesday as elevated breeziness combine with very low RH values. Afternoon breeziness will peak at 20-25 mph, highest across the AZ higher terrain areas. MinRHs will bottom out near 10% with poor overnight recoveries. Heading towards the middle to latter half of the work week, winds will be lighter, decreasing the overall fire weather threat. However, with MinRHs continuing to bottom out in the single digits to lower teens, even some marginal breeziness, can create localized elevated fire weather conditions.

PSR WATCHES/WARNINGS/ADVISORIES

AZ...None. CA...None.