textproduct: NWS Phoenix

UPDATE

00Z Aviation Discussion

KEY MESSAGES

- Slightly above normal temperatures will persist today before warming closer to 10 degrees above normal over the weekend and early next week as high pressure builds over the region.

- Some gusty northerly winds will linger along the Lower Colorado River Valley through this afternoon.

- There is a chance of a few showers and storms Sunday and Monday across the eastern Arizona high terrain.

SHORT TERM /Today through Sunday/

Latest water vapor satellite imagery and objective analysis depict a potent upper-level shortwave trough traversing the northern Plains while upper-level ridging is encroaching into the Pacific Northwest. This pattern configuration is leading to a strong surface high pressure across the Great Basin Region and thus strong northerly winds along the Lower Colorado River Valley area, where gusts in excess of 35-50 mph along with localized dust channels were observed earlier this morning. The overall winds will gradually diminish through the rest of the afternoon as the pressure gradient relaxes. Afternoon high temperatures will top out in the mid to upper 80s across the lower deserts, which will be about 3-6 degrees above normal for early April.

Heading into the weekend, as the overall ridge axis sets up along the interior western CONUS and upper-level height fields rise in response, temperatures will be on warming trend. Afternoon highs on Saturday will generally top out near 90 degrees before warming even further into the middle 90s for Sunday. Undercutting the ridge will be a weak shortwave trough moving in from the subtropical Pacific on Sunday while at the same time, easterly low-level flow will cause an increase in moisture across the eastern third of AZ with model guidance indicating PWATs rising to 200% of normal. This will likely be enough to spark some showers and isolated storms across the eastern third of AZ Sunday afternoon/evening, mainly across the Mogollon Rim and White Mountains. However, some isolated convection cannot be ruled out across eastern Gila County, where NBM PoPs range between 10-20%.

LONG TERM /Monday through Thursday/

Moisture introduced into the region Sunday will linger through Monday as PWATs will continue to remain near 200% of normal. Thus, there will likely be another round of afternoon convection, focused mainly across far eastern AZ. Otherwise, with upper-level ridging remaining situated over the region, temperatures through the middle of the week will remain steady state with readings generally in the 90s across the lower deserts. By late next week, models are hinting at another troughing feature approaching the region, which will likely cause a cooling trend with temperatures retreating into the 80s for afternoon highs.

AVIATION

Updated at 2310Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT: No major aviation concerns are expected during the TAF period. Winds will follow a familiar directional progression with the only differences being an earlier than usual switch to an E'rly component and directions favoring a more NE direction that what is typically seen. However, terrain affects may shift winds back to W'rly component overnight, mainly at KPHX and KIWA, though some uncertainty remains regarding this atypical shift. Regardless, E'rly winds will be favored once again Saturday morning, with perhaps a brief wind of marginal breeziness during that timeframe. Some gusts around 20 kts also cannot be ruled out for KSDL and KDVT this evening. SCT to perhaps BKN skies will be common throughout the forecast with bases remaining aoa 18k ft.

Southeast California/Southwest Arizona including KIPL and KBLH: Strong winds will continue to subside through this evening with only lingering gusts around 20-25 kts at KBLH being the main aviation concerns over the next 24 hours. NW/WNW'rly directions will be favored at each site through night before veering to the N/NNE late Saturday morning. SCT to sometimes BKN bases aoa 18k ft will be common over the region through most of the TAF period before clearing takes place Saturday afternoon.

FIRE WEATHER

Generally dry weather and above normal temperatures will persist during the next several days. Afternoon MinRHs will fall to near 10% through Saturday before increasing slightly on Sunday and Monday as moisture increases. The increase in moisture will result in some shower and thunderstorm chances, mainly confined to the eastern third of AZ. Some gusty northerly winds will linger through this afternoon along the vicinity of the Lower Colorado River Valley, resulting in some elevated fire weather concerns. Lighter winds are expected on Saturday before easterly winds increase Sunday morning, particularly across the higher terrain areas of south-central AZ. Lighter winds return for early next week.

PSR WATCHES/WARNINGS/ADVISORIES

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