Area Forecast Discussion
Issued by NWS Phoenix, AZ
Issued by NWS Phoenix, AZ
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950 FXUS65 KPSR 211254 AFDPSR Area Forecast Discussion National Weather Service Phoenix AZ 554 AM MST Fri Nov 21 2025 .UPDATE...Updated 12Z Aviation Discussion. && .KEY MESSAGES... - Scattered showers, with pockets of moderate to heavy rainfall, will be common across southeast California and southwest Arizona today. A few isolated thunderstorms are also possible. - A Flood Watch is in effect for southeastern California and southwestern Arizona through 11 pm PST Friday night/12 am MST Saturday morning. - The weather system will then push eastward Saturday and Sunday bringing scattered showers to central and eastern Arizona. - Temperatures will remain below normal this weekend and return to near normal as early as Tuesday. && .SHORT TERM /TODAY THROUGH SUNDAY/... Early this morning upper level water vapor satellite imagery and objective analysis show a deep upper level closed low straddling the coast of central CA and a surface low straddling the southern CA coast. This low will continue to dive southward through the day today and eventually stall out just off the northern coast of the Baja late tonight. This low has already brought scattered light showers to SE CA and the Lower CO River Valley early this morning. This system has raised PWATs into the 0.7-0.9" range across SE CA and SW AZ, with the highest PWATs in SE CA. Even though PWATs have been on the rise, the lower levels are still fairly dry. Forecast soundings show this and it is evident in observed rainfall amounts, over the past few hours, generally less than 0.1". The lower levels will become more saturated throughout the morning as the low continues to push moisture into the region. Once the lower levels become saturated, that will lead to better/more efficient rainfall rates. With the low staying along the coast today rain chances will be confined to SE CA and SW AZ leading to prolonged periods of rainfall across those areas. Forecasted rainfall totals of 0.50- 1.00" with higher amounts expected along terrain features and areas that receive more moderate to heavy rainfall. Due to these QPF totals and that the WPC has the area in a Slight Risk of excessive rainfall, a Flood Watch remains in effect through 11pm PST/12am MST tonight. MUCAPE values will be around 100 J/kg, so a few isolated thunderstorms will be possible, but most activity will be just showers. PWATs will remain around 0.5-0.6" across central and eastern AZ today. This in combination with the center of the low, and it`s associated vorticity, remaining along the coastline no rainfall is expected across eastern AZ and little to no rainfall is expected across central AZ. Any activity will remain light/sprinkles and most may only be virga showers. Western Maricopa County has the best chance of picking up a couple hundredths of measurable rainfall today. The center of the low will move into SW AZ by early Sunday morning and move northeastward through the day. Activity will linger through Saturday morning across SE CA and into Saturday afternoon across SW AZ before ending as the low pressure system moves east of these locations. As for central and eastern portions of AZ, PWAT values will remain in the 0.5-0.7" range through Saturday morning, keeping rain chances less than 10%. Again, minimal accumulations are also expected as any activity may just be virga showers through Saturday morning. By Saturday afternoon, when the center of the low pressure system moves into central AZ, PWATs will raise to 0.7-0.9" range (180-210% of normal). PWATs will be around 0.6-0.8" across the higher terrain in eastern AZ. This is when the best chance for showers will be across central (50-60%) and eastern AZ (80-90%). Models show no instability with this round of activity, so it should remain as just showers and no thunderstorms across central and eastern portions of the state. The low will be east of AZ Sunday night and quickly advect into the Plains on Monday. PWAT values will fall back below 0.7", and with the low and its associated forcing east of us rain chances across our region will be back to zero by Sunday night. For Saturday-Sunday, rainfall totals of 0.00-0.30" are currently forecasted for the lower deserts of south-central AZ and 0.30-0.60" across the foothills and higher terrain of eastern AZ. In addition to the rain chances, this low pressure system will also keep temperatures below normal through the weekend. Lower desert communities will see afternoon high temperatures in the 60s to around 70 degrees today through Sunday. Higher terrain areas will see afternoon high temperatures ranging from the upper 50s to the upper 60s today through Sunday. Morning low temperatures will range from the mid 40s to mid 50s across the lower deserts and range from the upper 30s to mid 40s across the higher terrain. && .LONG TERM /MONDAY THROUGH THURSDAY/... As we move into next week calm and tranquil weather conditions make a return to the Desert Southwest. The low pressure system that will bring rain to the region this weekend will be well to the east of the region by Monday. In the wake of the low pressure system, heights aloft will be around 574-577 dm on Monday slowly rising to around 578-581 dm by Thursday. This will result in a gradual warming trend through the workweek, with temperatures returning to near normal as early as Tuesday. Across the lower deserts afternoon high temperatures are forecasted to range from the mid 60s to low 70s rising to the low to mid 70s by the end of the workweek. For the higher terrain areas, afternoon highs on Monday will be in the low 60s rising to the upper 60s to low 70s by the end of the workweek. Additionally morning lows will range from the mid 40s to low 50s across the lower deserts and in the low to mid 40s across the higher terrain through the workweek. With rising heights aloft, forecast confidence is very good that dry conditions will prevail through this coming workweek. && .AVIATION...Updated at 1250Z. South Central Arizona including KPHX, KIWA, KSDL, and KDVT: Winds will remain aob 8 kt through the TAF period. Current easterly winds will go N/NE this afternoon before going back easterly during the overnight hours. At KPHX, a brief period of southwesterly winds are expected during the late evening hours tonight. CIGs will remain aoa 15 kft with scattered decks down to 7 kft possible. Dry conditions are expected, however, some VCSH/-SHRA will be possible this afternoon but this activity is expected to stay west of the terminals. Southeast California/Southwest Arizona including KIPL and KBLH: Periods of SHRA are expected to continue through the entire TAF period. VIS is expected to remain at or above 6 SM for the majority of the TAF period, however, if a more moderate shower moves over a terminal VIS may briefly be reduced to 3-5 SM. CIGs are expected to remain aoa 5 kft until around 3Z when they are expected to drop to around 4 kft. However, FEW-SCT clouds down to 1-3 kft are possible. Wind speeds will generally be aob 8 kt, but gusty and erratic winds are possible if any convective showers or TS pass near the terminals. Current NE`rly winds at KBLH will go N`rly this evening. Current E`rly winds at KIPL will go NE`rly this afternoon and then N`rly this evening. && .FIRE WEATHER... Below normal temperatures and elevated moisture will remain in place keeping MinRHs in a 40-70% range following excellent overnight recovery greater than 80%. Locally gusty winds upwards of 20 mph will be possible at times, though weaker wind speeds will be more common through the period. A weather system will be moving mainly across the western districts today leading to very good chances for wetting rains with more scattered shower activity across the eastern districts Saturday through Sunday. Temperatures will mostly remain below normal through the weekend with humidities staying elevated. Temperatures will return to near normal as early as Tuesday. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...Flood Watch through this evening for AZZ530>533-535-536. CA...Flood Watch through this evening for CAZ560>570. && $$ SHORT TERM...Berislavich LONG TERM...Berislavich AVIATION...Berislavich FIRE WEATHER...Berislavich