Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
396 FXUS65 KTWC 251714 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 1014 AM MST Tue Jun 25 2024 .SYNOPSIS... Southeast Arizona will continue to see enough moisture for a daily chance of thunderstorms into next week. Some storms will generate strong winds and locally heavy rain. Temperatures will heat up a few degrees by the middle of the week as high pressure builds overhead. Looking into July, the pattern is favoring active weather as additional moisture will likely move into the area. && .UPDATE... The current forecast is still on track for this afternoon and evening. The moisture is still here with the latest 12Z sounding this morning showing 1.8 inches of PW. To put this number into context, based on sounding climatology, we are currently well above the 90th percentiles and daily maximum for PW that is 1.44 inches. With the passage of the Mesoscale Convective Vortex early this morning, the atmosphere is a tad worked over to produce any stronger storms this afternoon and evening. Behind this MCV, there is an area of subsidence, or sinking air aloft, that will inhibit today`s afternoon and evening thunderstorms from getting too strong. As the remnants begin to move northward, the areas that are getting clearer first, areas south and east of Tucson have the best storm chances for this afternoon and evening. CAMs are in agreement with the best storm chances being fairly limited to these areas. As for timing, this all depends on when the clouds are able to move out and how long it takes for the atmosphere to overcome the convective inhibition, but CAMs are showing some development over the higher terrain around 1-2pm and forming in the valleys around 3-4pm continuing into the evening hours. Similar to yesterday, the main hazards with any thunderstorm will be locally heavy rainfall that can lead to nuisance flooding, as storms will stay very close to areas of formation with slow storm motion. Strong gusty winds are possible, but not the main hazard of focus today and will be isolated to the strongest storms of the day. && .PREV DISCUSSION... /issued 210 AM MST Tue Jun 25 2024/ && .DISCUSSION...Merging outflows were able to take advantage of remnant elevated CAPE over lower elevations from Tucson westward over the past several hours. In addition, a convective complex just south of the border is pushing additional debris could with embedded showers up from the south this morning. Trends will continue to slowly weaken through early morning hours. A remnant MCV will drift north across the area today, with some subsidence in it`s wake. We`ll also start to see some mid level warming as the high center reconsolidates near the area over the next 36 hours. With this in mind, overall we`re expecting fewer storms around as the atmosphere recovers into mid and late afternoon hours. We may be watching another strong complex in northwest Mexico try to push an outflow up from the south and southeast in the evening hours. With the ridge strengthening, we`ll heat up a few degrees but should have enough moisture to take the edge off and avoid any heat headlines. As larger scale features become less favorable for moisture import, we`re getting nice reinforcement from active complexes sending deep outflows up from Sonora and northwest Chihuahua. Meanwhile we`re easily maintaining dewpoints in the 60s with precipitable water values ranging from about 1.4 inches east to 1.9 inches west. Keep an eye out for additional (but more modest) gulf surge activity by this weekend. && .AVIATION...Valid through 26/12Z. SCT SHRA with ISOLD TSRA through 25/13Z. SCT TSRA will develop again after 25/20Z. Brief MVFR conditions possible with storms. Winds generally remain below 10 kts through the forecast period, except for gusty outflow winds from storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER... Relatively deep moisture will keep RH values on the higher side into next week, along with daily chances for thunderstorms. Moisture is expected to be deep enough for some storms to generate locally heavy rain. Winds should generally remain below 15 mph each afternoon, though occasional gusts to 20 mph are possible. Stronger erratic outflows with some thunderstorms. && && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Tetrault Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson