454 FXUS65 KPSR 231713 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 1013 AM MST Sun Feb 23 2020 .UPDATE...Updated aviation discussion. && .SYNOPSIS... Shower activity will continue to dwindle through the morning hours. In the wake of the storm, below normal temperatures are expected Sunday along with isolated showers across the higher terrain north and east of Phoenix. A return to near normal temperatures is likely early next week, followed by a warming trend later in the week as high pressure builds across the intermountain West. && .DISCUSSION... Latest objective analysis shows the center of an upper low positioned just to our north with a trough axis slicing through western Maricopa County. This system will continue eastward through the day and eventually exiting Arizona later today. Showers have persisted through 330AM (MST) with radar trends remaining active for a few more hours over east of Phoenix. Even though fast flow aloft has kept most showers from producing locally high rainfall rates, 0.50-0.75" of rain has fallen over an area stretching from Roosevelt Lake south towards Florence. A flood threat may continue for some areas, including Tonto Creek and the Superstition Mountains, as runoff continues to flow. Showers activity will decrease through morning with most of the lower desert remaining dry. Latest guidance keeps central Arizona temperatures below seasonal normals today in the mid 60s while areas farther west will reach the mid and upper 70s. Ensemble guidance continues to show strong ridging over the western US this week allowing daytime highs to reach the upper 70s/low 80s over much of the forecast area by the end of the week. && AVIATION...Updated at 1715Z. South-Central Arizona including KPHX, KIWA, KSDL, and KDVT: Typical diurnal wind patterns will take hold this afternoon with speeds peaking around 8-12 kts, then becoming very light to calm Sunday night as winds shift back towards the east. BKN cloud bases around 9-10 kft with SCT clouds around 5-6 kft are expected through this evening, before a decrease in cloudiness occurs into Monday morning. Isolated showers are possible in the afternoon, but should remain north and east of the metro. With very light to calm winds and clear skies Monday morning, there will be a potential for patchy fog development, but confidence is too low to add mention in the TAF. Southeast California/Southwest Arizona including KIPL and KBLH: Mid-level clouds across the area should clear by the afternoon as the upper disturbance exits. Winds will favor the west through the TAF period at KIPL, with speeds around 6-10 kts. KBLH will favor the west to southwest through the morning then shift more towards the northwest in the afternoon with some gustiness. Both terminals will experience light and variable winds Monday morning. && .FIRE WEATHER... Tuesday through Saturday: Conditions will be dry for the week with minimum humidities falling into the 10-25% range for most of the week. Overnight RH recoveries will also be meager. Wind directions will generally follow local diurnal/terrain influences. Breezy conditions are possible each afternoon with the strongest winds, 20-25 mph, occurring Wednesday. && .SPOTTER INFORMATION STATEMENT... Spotters should follow standard reporting procedures. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && $$ DISCUSSION...Deems AVIATION...Rogers/Benedict FIRE WEATHER...Deems |