textproduct: NWS Phoenix

UPDATE

Updated 12Z Aviation Discussion.

KEY MESSAGES

- Breezy to locally windy conditions will continue through this afternoon across the foothills and higher terrain east of Phoenix, where Wind Advisories are in effect through 2pm MST.

- Near to slightly above normal temperatures today will gradually warm to well above normal by the end of the workweek.

- Dry conditions will prevail across the region through at least this upcoming week.

SHORT TERM /TODAY THROUGH MONDAY/

Early this morning upper-level water vapor satellite imagery reveals that a rex blocking pattern has set up over our region. A closed low has set up over the Baja, with high pressure building into western CONUS. In between these two features an easterly jet has formed over the Desert Southwest. This jet will maximize this morning and slowly taper off through the afternoon. Wind gusts will generally be in the 20-35 mph range across the lower deserts, with the highest gusts across AZ. Even higher wind gusts are expected across the higher terrain east of Phoenix, with gusts upwards of 40-55 mph possible (highest gusts 50-55 mph are expected along ridgetops). Some isolated gusts into the 30s and 40s have already been observed early this morning in the foothills and higher terrain east of Phoenix. Winds will start to pick up later this morning, once the sun comes out, and the higher winds aloft can mix down to the surface. The highest wind gusts are expected during the late morning and early afternoon hours. Due to the strong gusty winds in the foothills and higher terrain east of Phoenix Wind Advisories will be in effect through the early afternoon (2pm MST). Winds will then taper off through the remainder of afternoon and evening as the closed low, and associated jet, shift SW of the area. Wind speeds will return to more seasonable levels this evening.

Aside from the strong gusty winds this morning into the afternoon, dry conditions will continue along with mostly clear skies and gradually warming temperatures. Temperatures this morning will largely be above freezing. However, some isolated sheltered valleys may see temperatures near or dip below the freezing point. Temperatures this afternoon are forecasted to be 2-4 degrees warmer than yesterday, with highs in the mid to upper 60s to near 70 degrees across the lower deserts and in the mid 50s to low 60s across the higher terrain. Further warming is anticipated on Monday with afternoon highs in the upper 60s to low 70s across the lower deserts and in the upper 50s to mid 60s across the higher terrain.

LONG TERM /TUESDAY THROUGH FRIDAY/

Ensemble members are in good agreement that the rex blocking pattern will hold through at least the beginning of the upcoming workweek before the low finally starts to break down during the middle to latter half of the workweek. At the same time, the high pressure will maximize. As the high strengthens throughout the week, heights aloft will gradually rise resulting in gradually warming temperatures. The warmest temperatures of the week are forecasted for the end of the workweek, coinciding with when the high is forecasted to maximize. Afternoon high temperatures on Tuesday are forecasted to be in the low to mid 70s across the lower deserts and in the 60s across the higher terrain. Then for the latter half of the week high temperatures warm into the mid to upper 70s to near 80 degrees across the lower deserts and in the mid 60s to low 70s across the higher terrain. Temperatures in this range will be 7-10 degrees above normal for the middle of January. Additionally morning lows will be on the rise, going from the 40s (30s) across the lower deserts (higher terrain areas) on Tuesday to the upper 40s to low 50s (low to mid 40s) to end the workweek. Dry conditions will also continue through this upcoming week.

AVIATION

Updated at 1155Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT: The main aviation concern this TAF period is gusty winds during the late morning and afternoon hours. Winds through the whole TAF period will favor a easterly/northeasterly direction. Wind speeds through the mid morning will generally be around 10-15 kt. By the mid to late morning hours winds will start to gust into a 25-30 kt range. Some gusts may go into the 30-35 kt range. Winds will taper off back down to around 10 kt by the early evening timeframe. Winds will lessen even more, down to aob 6 kt, during the overnight hours. Skies will remain clear.

Southeast California/Southwest Arizona including KIPL and KBLH: No major aviation concerns are expected throughout the TAF period under clear skies. Winds at KBLH will exhibit a northerly component the whole TAF period. At KIPL, current westerly winds will go north/northwesterly late this morning before going back westerly this evening. Wind speeds will generally be aob 7 kt at KIPL and generally be in a 8-15 kt range at KBLH through the whole period.

FIRE WEATHER

Temperatures will be near to slightly above normal today and will gradually warm through the workweek. Temperatures will go well above normal by the middle of this coming week. MinRH values of 15-35% and overnight recoveries of 40-70% will continue through this coming week. Breezy to locally windy conditions will continue today. The highest gusts will be across the eastern districts, especially ridgetops, where gusts in excess of 40 mph are likely through the early afternoon. Wind speeds will return to more seasonable levels this evening and continue into next week. Winds will maintain a northeasterly to easterly prevailing direction today and possibly into early next week.

PSR WATCHES/WARNINGS/ADVISORIES

AZ...Wind Advisory until 2 PM MST this afternoon for AZZ552-558.

Wind Advisory until 2 PM MST this afternoon for AZZ547-555-557- 561-562.

CA...None.