565 FXUS65 KPSR 021735 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 1035 AM MST Mon Jun 2 2025 .UPDATE...Updated Aviation Discussion... && .DISCUSSION... Key Messages: - Lingering showers and a thunderstorm or two early this morning across the Phoenix metro will lift to the north, with isolated to scattered chances in higher terrain during the daytime hours - Another round of isolated light showers possible Tuesday night and Wednesday - Below normal temperatures today will quickly rebound towards normal through the middle of the week and then above normal late week The majority of the region enjoyed some rainy conditions on Sunday, as most areas in south-central Arizona saw at least 0.25". The more robust shower and isolated storm activity is occurring early this morning, with the primary driver being the low center passing over the Phoenix metro that is tapping into some uninhibited instability of around 500-100 J/kg according to the latest SPC Mesoanalysis. The already moistened profiles from yesterday`s rains is allowing for more efficient rains to reach the surface, resulting in impressive amounts across the West Valley nearing or exceeding 1.00" in some areas with training showers. Moderate to heavy rains will continue to lift to the north and east along with the low center, with drier air filtering into the region, resulting in limited shower activity primarily across the higher terrain north and east of Phoenix later today. The upper level closed low will eject eastward throughout the day, as drier air begins to erode the tropical moisture across the region. Thus, even though there is another troughing feature following this current low, there is not much optimism of more rain potential beyond today across the region, although the best chances (10-25%) remain on Wednesday as the closed low begins to migrate eastward across the region. However, this feature remains considerably dry in the mid to upper levels, thus kept rain to just isolated chances across the northern portions of the CWA on Wednesday. General longwave troughing will continue to linger across the Desert Southwest going through late week, although the exiting mid-week trough will result in mid-level heights rebounding back towards climatological norms near 582-585 dam. Sub-tropical ridging begins to build across northern Mexico and southern TX mid to late week, with ensembles showing a pretty expansive 591 dam area Thursday and Friday. Ensembles then seem to be in pretty good agreement of this ridge eroding the longwave troughing late week and into the weekend, with mid-level heights building into the 585-588 dam range by this weekend. Thus, temperatures will be warming throughout the week, with today being the coolest (below normal). Near normal temperatures through the middle of the week will precede near to above normal temperatures, as the NBM IQR nears the mid to upper 100s across the lower deserts over the weekend. Thus, a return of Moderate HeatRisk to the region by this weekend seems inevitable due to the good agreement of the pattern evolution through this weekend. && .AVIATION...Updated at 1735Z. South Central Arizona including KPHX, KIWA, KSDL, KDVT: No additional rainfall is expected over the next 24 hours and skies will feature FEW to SCT cumulus through this afternoon with bases rising from 4-5K ft AGL now up to 7-8K ft AGL this afternoon. Skies then clear tonight. Light variable winds now will establish out of the west by early afternoon with wind speeds mostly around 5-10 kts. Light easterly winds return tonight after midnight. Southeast California/Southwest Arizona including KIPL and KBLH: No aviation impacts are expected through the period with mostly clear skies. Expect southeasterly winds for much of the period at KIPL, with the exception of some southwesterly winds this evening, and southerly winds for the entire period at KBLH. && .FIRE WEATHER... Lingering wetting rains (50-80%) with a few isolated thunderstorms across the eastern districts this morning will slowly shift eastward throughout the day. Lingering showers are possible on Tuesday and Wednesday across mainly the higher terrain in the eastern districts, but wetting rain chances remain low (15% or less). This abnormally wet pattern will quickly transition back to more typical dry conditions and seasonable temperatures mid to late week, as minRH`s degrade from 25-50% to 15-25% by mid-week with overnight recoveries remaining good to excellent (above 40%) through this period. Late week RH`s will continue to degrade near 10-15% and overnight recoveries becoming poor to fair (20-40%). Outside of erratic, gusty winds near showers and storms early in the week, winds should be fairly typical for late spring with the usual afternoon upslope gustiness. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ DISCUSSION...Young AVIATION...Benedict/Kuhlman FIRE WEATHER...Young/18