Area Forecast Discussion
Issued by NWS Atlanta, GA
Issued by NWS Atlanta, GA
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172 FXUS62 KFFC 041722 AFDFFC Area Forecast Discussion National Weather Service Peachtree City GA 122 PM EDT Thu Jul 4 2024 ...New 18Z Aviation Discussion... .SHORT TERM... (Today through Friday) Issued at 435 AM EDT Thu Jul 4 2024 At a glance: - Hot temperatures with a Heat Advisory for much of the area today. Heat will likely continue through Friday. - Increasing chances of showers and storms, particularly on Friday. An upper ridge of high pressure will remain anchored over the area today. The ridge position will shift a bit S for Friday as a weak trough moves into the W Great Lakes and upper MS Valley. At the surface, high pressure will weaken a bit today. A cold front will approach the area from the NW on Friday with increasing shower and thunderstorm chances. For today, scattered showers and thunderstorms are expected generally from near and W of the Atlanta metro area S to Columbus and Macon. For Friday, shower and thunderstorm chances will increase from the NW ahead of the approaching front. The best chances will be from the Atlanta metro area NW. Organized severe weather is not expected. However, isolated strong storms are possible this afternoon. Due to the upcoming holiday, have gone ahead and hoisted an advisory for all areas save the NE. loading producing gusty winds in the strongest storms. On Friday, increased instability, a slight uptick in effective shear, and increasing frontal convergence may bring a slight increase in the likelihood of strong storms to the NW. Very light low and mid- level winds will lead to slow storm motion today. As a result, isolated heavier rainfall totals are certainly possible. The big story will continue to be hot temperatures. High temperatures today will be in the lower to upper 90s across most of the area except the NE corner. These temperatures will couple with dew points in the mid 70s to produce heat indices as high as 109 this afternoon. The warmest temperatures are expected over the E half and NW corner of the area. The highest dew points during this time period are expected across the SW portion of the area as southerly flow continues to tap into Gulf of Mexico moisture. The different areas of max temperatures and dew points will lead to rather variable heat index values, but many areas are expected to reach low end Heat Advisory criteria. Heat indices are forecast to increase a bit for Friday. However, there is some uncertainty regarding increasing rain chances and associated cloud cover. As a result, will defer to the day shift regarding any possible extension of the Heat Advisory. /SEC && .LONG TERM... (Friday night through Wednesday) Issued at 435 AM EDT Thu Jul 4 2024 Looking at a break down of the 500 mb ridging over our area as the high pressure shifts eastward and a trough begins to deepen into the mid MS valley into Friday. As this trough moves further eastward and the associated surface low moves into the Ohio valley, a cold front looks to move into the Tennessee Valley by Friday increasing rain chances over north Georgia Friday into Saturday. The long term begins in the middle of that transition as the front looks to be solidly over central Georgia Saturday into Sunday as it slowly sinks southward. This is shown in the increased rain chances through the weekend. Models are indicating PWATs at 2"+ over the area into the weekend, so again any storms will likely be efficient rainfall producers and we`ll have to keep an eye on the flooding potential although rainfall amounts are limited at this time. CAPE values ~1500-2500 J/KG are currently showing up in the ensembles, so thunderstorms will definitely be a risk as well through the weekend. Towards the beginning to middle of next week, things are a little uncertain when it comes to rainfall potential. The troughing does look to stay solidly in place though over the central US with the high pressure of to our east. With this pattern and the increased moisture being brought in with southwesterly winds, have kept increased PoPs through the middle of the week. This increased moisture is also the reasoning behind the increased heat indices through the long term. Currently looking at heat indices from 100- 107 through the long term, although increased rainfall may help reduce those values. Temps are forecast to be in the mid to upper 90s through the weekend and with the moist airmass (dewpoints in the mid 70s), heat indices will need to be monitored for potential heat advisories for the July 4th weekend. Hernandez && .AVIATION... (18Z TAFS) Issued at 114 PM EDT Thu Jul 4 2024 Isolated thunderstorms will remain an concern in the region through 06Z Friday. The probability of storms will be highest at the TAF sites before 00Z Friday. Isolated MVFR conditions (ceilings 2500-3000 ft AGL and visibility of 2-5 SM) and erratic winds may occur with any thunderstorms. Prevailing VFR conditions are expected after 00Z Friday, then isolated IFR/MVFR conditions (ceilings 800-2500 ft AGL) may develop between 09Z and 15Z Friday. Winds should remain light (7 kt or less) from the southwest through 18Z Friday. //ATL Confidence...18Z Update... Moderate overall confidence in the ATL TAF. Low confidence in the potential for thunderstorms at ATL before 03Z Friday. Low confidence in the ceilings at ATL between 10Z and 14Z Friday. Moderate confidence in the potential for thunderstorms after 20Z Friday. Albright && .PRELIMINARY POINT TEMPS/POPS... Athens 76 95 74 94 / 10 70 60 60 Atlanta 77 94 75 93 / 10 70 60 60 Blairsville 71 88 70 87 / 20 80 50 50 Cartersville 76 94 73 92 / 10 70 50 50 Columbus 77 96 76 94 / 20 70 60 80 Gainesville 76 93 75 92 / 10 70 60 60 Macon 76 96 75 95 / 10 60 60 70 Rome 76 94 75 93 / 20 80 40 40 Peachtree City 75 94 73 92 / 10 70 60 60 Vidalia 75 97 76 95 / 10 40 30 70 && .FFC WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 7 PM EDT this evening for GAZ001>005-011-012- 019>021-024-025-027-030>039-041>062-066>076-078>086-089>098- 102>113. && $$ SHORT TERM...SEC LONG TERM....Hernandez AVIATION...Albright