Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
317 FXUS65 KTWC 301552 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 852 AM MST Sun Jun 30 2024 .SYNOPSIS...Active monsoon pattern for the next 7 days will bring daily chance of showers and thunderstorms. Some storms will generate strong winds and locally heavy rainfall. && .UPDATE...Latest visible satellite imagery shows an MCV from the remnants of the overnight convection across far northern Sonora, to the south of western Pima County. Still quite a bit of cloud cover from Tucson westward with mostly sunny to partly sunny skies east of Tucson. As the morning progresses, expect increasing sunshine from east to west as the MCV moves farther away. Meanwhile, the next disturbance is coming in quickly and seen on WV imagery near El Paso. 12Z HREF/CAMs have initialized the ongoing situation well and develop the next round of convection as early as around 1 PM from Tucson eastward as the next disturbance approaches and helps enhance lift. Still looking like an active afternoon/evening across much of our forecast area. Convective parameters look favorable with MLCAPE around 1000 J/KG and DCAPE around 1000-1300 J/KG to produce strong outflow winds. The Flash Flood Watch and Blowing Dust Advisory that the previous shift issued also still look good. Forecast is in good shape. No updates this morning. See previous discussion below for additional information. && .DISCUSSION...Scattered showers/isolated thunderstorms continue to push west this morning, the last day of June, associated with a disturbance aloft moving across northern Sonora MX. Have seen some strong wind gusts from either thunderstorm (72 mph at Pioneer Air Field) or with the outflow (63 mph at Nogales airport, 62 at Mt Hopkins, 55 mph at Nogales airport and 44 mph at Tucson Intl). These showers will gradually end from east to west this morning with cloud cover also decreasing as the morning progresses. This sets us up for an active afternoon/evening. HREF continues to paint central/eastern Pima, Santa Cruz and western Cochise county for threat of heavy rain with deep moisture over the area. WPC has this area under slight risk of excessive rainfall this afternoon/evening. Thus have decided to hoist a Flash Flood Watch from 4 pm to 11 pm for cntrl/ern Pima county, all of Santa Cruz county, western portions of Cochise county and southern portions of Pinal county. Some storms today will also be strong to severe with outflows developing areas of blowing dust, especially west and northwest of Tucson. Thus have also hoisted a blowing dust advisory for above mentioned area from 3 pm to 10 pm. Monday will be dependent on how worked over the atmosphere is from todays storms. Daily chances of showers/storms will exit for the rest of the work week. High temperatures for the most part will be around or slightly above of normal as we start July. && .AVIATION...Valid through 01/12Z. SCT-BKN clouds at 8-12k ft AGL thru the fcst period. SCT -SHRA and ISOLD -TSRA movg W and dissipating by 30/17z then redvlpg Aft 30/20z to SCT -SHRA/-TSRA with brief MVFR conds nr storms. SFC winds 10 kts or less with the occasional afternoon gusts, except stronger due to gusty outflows from storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Relatively deep moisture will stick around through the forecast period. Scattered showers and thunderstorms this afternoon and tonight. The upcoming week will see daily chances of afternoon and evening showers and thunderstorms. Strong erratic gusty winds of 40 mph or higher can be expected with any storm development, along with locally brief heavy rainfall. Outside of thunderstorm winds, 20-foot winds will generally be 15 mph or less each afternoon with the occasional gust of 20 mph. Min RHs will generally be around 20% in the valleys and 30s in the mountains with good overnight recoveries. && .TWC WATCHES/WARNINGS/ADVISORIES... Blowing Dust Advisory from 3 PM this afternoon to 10 PM MST this evening for AZZ502-504>506. Flood Watch from this afternoon through this evening for AZZ502>507-513>515. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson