FXUS65 KPSR 270522 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 1022 PM MST Sun Oct 26 2025 .UPDATE...06Z Aviation Discussion. && .KEY MESSAGES... - Dry and tranquil weather will prevail throughout the week with temperatures near to slightly above normal. && .SHORT TERM /Today through Tuesday/... A strong zonal jet core was punching into the northern California coast and Great Basin early this afternoon placing the forecast area under a warming, subsident regime. This SW Conus quasi-zonal flow pattern will persist over the next 48 hours with H5 heights increasing from near 582dm closer to a 585-588dm range. A tendency towards amplified ridging will materialize towards the middle of the week as northern stream shortwave energy digs into the SE Conus in response to growing western hemisphere blocking. This common autumn pattern will assure a continuation of dry, tranquil weather; and excellent model agreement yields very high forecast confidence of temperatures hovering a few degrees above the daily normals. && .LONG TERM /Wednesday through Sunday/... During the middle of this week, subtropical ridging will start to push into Arizona causing H5 heights to rise to around 588-590 dm, which in turn will lead to warming temperatures. Afternoon high temperatures will likely be in the low to mid 90s across the lower deserts and in the low to mid 80s across the higher terrain through Thursday. Models show H5 heights maxing out on Wednesday, making Wednesday forecast to be the hottest day of the week. These midweek temperatures are forecasted to be around 5-8 degrees above normal, but 4-5 degrees shy of record levels. By the end of the week, models show a weak shortwave trough moving into our region. This weak shortwave looks to lower heights aloft with H5 heights falling to around 582-585 dm resulting in a slight cooling trend of a couple degrees. Temperatures are forecasted to fall back into the mid to upper 80s to near 90 across the lower deserts and in the low to mid 80s across the higher terrain to end the workweek and continue through the weekend. Forecast confidence does start to go down next weekend as the GEFS shows high pressure trying to build back in which would result in warming temperatures. Either way, dry conditions look to continue for at least the next 10 days. && .AVIATION...Updated at 0520Z. South Central Arizona including KPHX, KIWA, KSDL, and KDVT; and Southeast California/Southwest Arizona including KIPL and KBLH: No aviation weather concerns will exist through the forecast period under mostly clear skies. Winds will follow normal diurnal trends along with periods of calm and vrb conditions. Wind speeds will remain very light, around 7 kts or less at all terminals. && .FIRE WEATHER... Temperatures will remain largely unchanged today and tomorrow with a slight warming trend during the middle of the week. Temperatures then look to cool a few degrees by the end of the workweek and heading into next weekend. Either way temperatures look to be 4-8 degrees above normal through the week, maxing out on Wednesday. MinRHs today and tomorrow will be around 20% for the lower deserts to around 25% over the higher terrain areas. Then on Tuesday through the remainder of the week, minRHs fall to 10-15% for the lower deserts to around 20% for the higher terrain areas. Winds over the next week will generally follow their typical diurnal tendencies with limited afternoon upslope gustiness. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ SHORT TERM...18 LONG TERM...Berislavich AVIATION...Salerno FIRE WEATHER...Berislavich