textproduct: NWS Phoenix

KEY MESSAGES

- Slightly above normal temperatures will persist through today before readings warm again this weekend returning to around 10 degrees above normal.

- Increasingly gusty north winds will impact locations through the lower Colorado River valley this morning with localized blowing dust possible. - There is a chance of a few showers and thunderstorms early next week across the eastern Arizona high terrain.

SHORT TERM /Today through Saturday/

Mid-level water vapor imagery shows weak troughing across the Desert SW with quasi linear flow across the region, additionally, ridging can be seen building in the Eastern Pacific. Even with broad troughing over much of Western CONUS our CWA is still under slightly positive H5 height anomalies with heights expecting to be near 574- 577 dam today and increasing to 576-579 dam by tomorrow afternoon. This will lead to temperatures for today to be in the upper 80s across the lower deserts and in the upper 70s in the higher terrain areas. For Saturday, as heights aloft increase, afternoon highs will be in the upper 80s to lower 90s across the lower deserts and in the upper 70s in the higher terrain areas, with some localized areas over 80F. The aforementioned ridging in the Eastern Pacific will lead to a tightening in the pressure gradient causing northerly breezy to windy conditions along the Colorado River Valley. Current model guidance suggests peak winds at the surface to be near 35-45 mph early this morning and lasting into the late morning hours before weakening going into the afternoon hours. The highest wind speeds are expected to be along the ridge tops.

By Sunday heights aloft continue to increase as the ridge moves farther east and over the Desert SW. This will cause temperatures across the lower desert to climb back into the mid 90s, and lower 80s in the higher terrain areas. However, a short wave trough looks to progress across northwest Mexico and southern Arizona on Sunday. Along with this shortwave PWAT anomalies during this time are expected to rise to over 200% of normal in the eastern portion of the higher terrain. The latest NBM has lower PoP chances down from 30-40% to now around a 15-20% chance, with QPF totals near 0.01". Most of the forecasted QPF is further to the east, into Eastern Arizona into Western New Mexico.

LONG TERM /Sunday through Wednesday/

By Monday any moisture introduced to the region Sunday will begin to trend back towards normal, but looks to remain slightly above normal, generally around 100-130% of normal. This lingering moisture will help facilitate some cloud coverage over the region throughout the week. Temperatures throughout the week will be in the mid to upper 90s across the lower deserts. These temperatures are in response to ridging over the region throughout most of the workweek. By late into the week into the weekend models are hinting at another troughing feature approaching the region, which may help lower temperatures back towards normal.

AVIATION

Updated at 0525Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT: No major aviation concerns are expected during the TAF period. Winds will follow light and diurnal trends, though the typical E'rly shift tonight/Friday morning will occur later than usual. Confidence regarding wind directions decreases toward the end of the forecast window as an earlier than usual E'rly shift may give way to another W'rly shift. Given the nature of our typical diurnal winds, TAFs currently reflect an E'rly direction during this timeframe, with KPHX showing a VRB group later in the night to reflect the uncertainty of multiple directional shifts. Clear skies tonight will give way to increasing high cloud coverage by Friday morning.

Southeast California/Southwest Arizona including KIPL and KBLH: The main aviation concern over the next 24 hours will be breezy to windy conditions at both terminals. The strongest gusts are likely to be focused at KBLH where readings will near 30 kt Friday morning. Given these enhanced winds and the prevailing direction being from the north, reduced VIS in blowing dust cannot be ruled out, but confidence is too low to include mention BLDU in the TAF at this time. At KIPL, peak gusts out of the N/NNE between 20-25 kt will be more common. Clear skies will give way to increasing high base coverage by Friday morning.

FIRE WEATHER

Dry weather returns to the region with temperatures hovering slightly above normal through today. Minimum humidity levels are expected to fall closer to 10% today. Tonight overnight recoveries will deteriorate into a poor to fair 20-50% range. Enhanced wind gusts 30-40 mph will be possible in western districts early to late this morning creating elevated fire weather conditions, while other areas will only see modest afternoon breeziness. Lighter winds and temperatures rising to well above normal are then anticipated for the weekend. Moisture is expected to briefly increase across eastern Arizona this weekend potentially bringing chances for showers and thunderstorms across the higher terrain on Sunday.

PSR WATCHES/WARNINGS/ADVISORIES

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