textproduct: NWS Phoenix

UPDATE

Updated Aviation Discussion.

KEY MESSAGES

- Breezy to locally windy conditions for the foothill and higher terrain areas of the Desert Southwest will continue into Monday

- Dry conditions will prevail as temperatures rise toward well above normal levels by the middle of the week.

SHORT TERM /Today through Monday/

Current objective analysis reveals a Rex block setting up over the western tier of the CONUS which will be the main weather focus over the next few days for the Desert Southwest. The area of low pressure associated with this type of setup is currently centered over the Baja Peninsula and has helped set off some breezy to locally windy conditions for parts of the region due to the enhancement of the local pressure gradient. Elevated gusts are likely to persist into Monday, especially for foothills and higher elevations areas, as the gradient only relaxes slightly. Observations of 25-35 mph will be common for these areas with locally higher gusts closer to 40 mph possible for the highest ridge tops east of the Phoenix metro. However, due to the limited scope of advisory level winds, no wind products will be issued. After a chilly end to the previous week, temperatures will gradually climb back toward near and above normal levels by the start of the upcoming workweek as lower desert highs rebound into the upper 60s and lower 70s.

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 0545Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT: E'rly winds will prevail through Monday under FEW to SCT cirrus clouds. Winds tonight will remain elevated, sustained up to 5-10 kts, across parts of Phoenix, with lighter winds in sheltered locations like KSDL. Marginal LLWS impacts are expected tonight through early Monday morning, with shear magnitudes around 20-30 kts. E'rly wind gusts up to 15-25 kts will develop Monday morning beginning around 17Z and then gradually subside through the afternoon.

Southeast California/Southwest Arizona including KIPL and KBLH: No major weather issues will exist through Monday. Confidence is very good that a northerly wind component will be preferred at KBLH through the TAF period, while KIPL sees westerly winds during the overnight hours and northerly during the day. FEW to SCT cirrus will pass over the area through Monday.

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...None. CA...None.