Wednesday Evening Forecast

Forecast Issued by Justin Gibbs on 04/19/2006 at 4:01:21 pm CT

Mobile, Alabama 5 Day Forecast
Tonight	Tomorrow	Friday	Saturday	Sunday
	87°F	85°F	82°F	84°F
67°F		66°F	62°F	60°F
SW 5-10 mph	S 5-10 mph	SW 5-10 mph	NW 5-10 mph	SW 5-10 mph
0%	0%	20%	30%	0%

Detailed Forecast

Tonight… Partly cloudy, with patchy fog after 3 a.m. Low 67. Winds southwest 5-10 mph. Tomorrow... Partly cloudy. High 87. Winds south 5-10 mph. Thursday Night... Increasing Cloudiness. Low 66. Winds south 5-10 mph. Friday... Partly Cloudy with a 20 percent chance of showers and thunderstorms. High 85. Winds southwest 5-10 mph. Friday Night... Mostly cloudy with scattered showers and thunderstorms. Low 62. Winds south 5-10 mph. Chance of rain is 30 percent. Saturday... Mostly cloudy with scattered showers and thunderstorms. High 82. Winds northwest 5-10 mph. Chance of rain is 30 percent. Saturday Night... Mostly clear. Low 60. Winds northwest 5-10 mph. Sunday... Partly cloudy. High 84. Winds southwest 5-10 mph. Sunday Night... Mostly clear. Low 60. Winds southwest 5-10 mph.

Technical Discussion

Forecast Discussion (Wednesday through Sunday): Right Now... At the surface a ridge is centered over the Northwestern Carribean with an axis streching northwest into the northcentral Gulf...as a sfc cyclone positiosn itself across northern Alabama. Ridging/Zonal flow persists over the northcentral Gulf coast...allowing for another hot and humid day--with moderate southerly flow and continued moisture/warm air advection. Low level moisture ribbon exists as indicated by WV imagery and KLIX/KJAN/KCRP 12z sounding from about 800mb to essentially the surface...this has allowed for continued low/mid level clouds in the daytime heating. Downstream, vertically stacked closed low is centered over eastern South Dakota. Short Term... Impacts of sfc storm system over NRN AL/MS are expected to remain well north of the MOB area. Sfc ridging and a building ridge between 700/850mb have led to meager lapse rates and a large negative area on RUC soundings...this is echoed to some degree on KLIx 12z observed sounding and appears reasonable given handling of features aloft and actual wx. We look to remain in a light to moderate southerly flow for the next 24-36 hours ahead of our next sfc storm system this weekend. Td's continue to creep upward and MOS/going forecast low of 67 looks on target. SCT/BKN cloud coverage will likely persist to some degree even into the overnight hours. Fog will again be an issue as dewpoint depressions look to drop to 0/1 in the overnight hours with a light south wind. Thursday ridging continues to build in aloft with a bit of moisture still lingering at the lowest mandatory levels. MOS seems to cool us up quite a bit due to cloud cover. Given the extremely dry air just above 800mb do not believe we will see QUITE the coverage that is advertised as lower levels should mix enough to prevent full overcast so will continue with the going forecast high of 87 which is MOS consensus blend +1. Thursday night s/wv approaches from the west and moisture begins to build throughout the column...guidance brings us to nearly full overcast by 6-12z but will for now just slide the well suited "increasing cloudiness" ("punt") forward a period as that will most likely best describe what occurs with coverage building from 2/10 to around 6/10 by morning. Long Term... Guidance has shifted considerably today in the 12z suite of products as the upper level s/wv and assocaited sfc cyclone are now nearly 15 hours faster. 18z data also suggests a much faster solution with simliar FROPA timing to the 12z data. HPC suggests this solution is plausible to likely given the initialization of the system. WV imagery also indicates 12z guidance (esp NAM) has performed well with the positioning of the system through the first 9 hours of the model run. Will basically just slide everything up a period with 20 pops returning to the forecast on Friday and going 30/30 Fri/Sat leaving Sat evening dry. Am inclined to go a bit higher given the airmass ahead of the frontal system...with plentiful deep moisture and a relatively unstable overall airmass. However, given questions that obviously persist regarding timing will hold to our going 30s and later shifts can make adjustments as forecast confidence increases. System looks to have a minimal intrusion on our airmass at this latitude as a ridge quickly builds in behind the front swinging our winds back from the southwest and back into WAA pattern. Ridge builds in aloft and it looks as was previously mentioned we will return to tempeartures just above seasonal norms for next week. Will actually bump going forecast highs up a degree given substantial increase in mandatory heights indicated in 12/18z data.

Hazardous Weather

No hazardous weather is expected through the forecast period.