Thursday Morning Forecast

Forecast issued by Justin Gibbs on 10/19/06 at 1:29:38 am CDT

Mobile, Alabama 5 Day Forecast
Today	Friday	Saturday	Sunday	Monday
84°F	73°F	73°F	79°F	72°F
	60°F	56°F	63°F	60°F
SW 5-10 mph	N 5-10 mph	W 4-8 mph	S 5-10 mph	NW 10-15 mph
70%	0%	10%	40%	0%

Mobile, Alabama 5 Day Detailed Forecast

Today... Partly cloudy with showers and thunderstorms likely, especially in the afternoon. High 84. Winds southwest 5-10 mph. Chance of rain is 70 percent. Tonight... Mostly cloudy with showers and thunderstorms likely. Low 60. Winds west 10-15 mph. Chance of rain is 70 percent. Friday... Mostly cloudy early then clearing by afternoon. High 73. Winds north 5-10 mph. Friday Night... Mostly clear. Low 56. Winds north 4-8 mph. Saturday... Partly cloudy with isolated showers and thunderstorms possible in the late afternoon. High 73. Winds west 4-8 mph. Chance of rain 10 percent. Saturday Night... Partly cloudy with isolated showers and thunderstorms. Low 63. Winds southwest 5-10 mph. Chance of rain is 20 percent. Sunday... Partly cloudy with scattered showers and thunderstorms. High 79. Winds south 5-10 mph. Chance of rain is 40 percent. Sunday Night... Mostly cloudy with scattered showers and thunderstorms. Low 60. Winds northwest 7-14 mph. Chance of rain is 40 percent. Monday... Mostly cloudy. High 72. Winds northwest 10-15 mph.

Technical Discussion

Synopsis: 05z Surface analysis reveals a coldfrontal boundary draped across eastern Arkansas and far northwestern Mississippi, attached to a developing sfc cyclone over the MO Bootheel. Aloft very weak divergence coupled with a weak remnant boundary produced somscattered SHRA this evening but that has since subsided. Pronounced 200/700mb trof axis exists is analyzed from 0z RAOBs from the four corners region to northern Minnesota. Phasing subtropical/polar jet streak indicated from NRN TX to NRN NY at 300mb. Forecast Discussion (Thursday through Monday): Short Term... Storm system will progress eastward through the first two forecast periods. GFS/NAM is in relatively acceptable agreement regarding a 0-6z FROPA with the NAM leaning towards the latter. NGM/UKMET agree with the slower NAM while ECMWF tips its hat to the GFS. GFS is slightly weaker with the overall dynamics of the system but both seem reasonably analyzed so will for now go with a blend and assume a 4-5z FROPA. Thermodynamic profiles indicate a relatively unstable airmass will be in place as moisture return gets rolling during the day today with southwest winds at 5-15 mph pulling in rich gulf moisture (Buoys indicating Td's near 80). As previous shifts mentioned dynamic environment is not on par with what we saw Monday, however, speed shear and to some degree directional shear is still more than sufficient for organized thunderstorm development. The main threat today appears to be damaging winds and perhaps large hail. NAM/GFS forecast soundings point to about 15-20 degrees of low level turning with 0-3km SRH on the order of 150 m2/s2. This suggest the possibility of a few isolated tornadoes in the most vigorous updrafts but the storms will likely require some sort of additional boundary support to produce. More likely this will allow sufficient rotation of updrafts to allow for an enahnced hail production potential. Overall picture suggests the possibility of supercells at the onset of the episode likely coalescing into a squall line/MCS by nights end. Will go with 70/70 with afternoon/evening wording for the first two periods pop wise. Friday guidance/current analysis indicates rather quick column drying behind the frontal boundary/trof axis so will continue the PoP free going forecast. Going forecast appears on track for winds/temp/cloud cover through Friday night. Only question regards how far south the frontal boundary will push once it becomes paralell to the mean flow, for now guidance seems rather convinced it will clear the area entirely for F/FN and this solution appears reasonable and shows good continuity. Long Term... Boundary becomes a little less well behaved as we enter the weekend. GFS is still a bit more agressive with moisture return on the backside of the sfc ridge to the east. Will reduce the going 20 pop to 10 pop, but the boundary is extremely close to the coast and moisture is still begining to work in with GFS indicating 850/700mb RHs going above 80% by 12z Sunday, so will taper the SN pop to 20% given the slower moisture return trend of the GFS (which is more in line with NGM. Reinforcing frontal boundary pushes through Sunday afternoon ahead of a powerful upper level low. Sunday afternoon mean upper level flow becomes...and remains northwesterly and brisk. Strong northwesterly upper level flow will aide in providing a rather stark temperature contrast behind the boundary and push our temperatures to unseasonably cool levels for the start of the next work week. It should be noted MEX MOS has trended downward in each sucessive run for Tuesday mornings low now showing 48."

Hazardous Weather

Short Term (Today through Thursday) Organized showers and thunderstorms are expected tonight as a cold front approaches from the northwest. There is a chance a few of these storms may become severe, with damaging winds the main threat. Large hail, and an isolated tornado cannot be completely ruled out with this system. Long Term (Friday through Monday): No hazardous weather is expected at this time.

Astronomical and Climatological Data
Moon Phase Crescent Waning Sunrise 6:57 AM Sunset 6:16 PM	10/19/06 Normal High Record High Normal Low Record Low Temperature 78°F 88°F (1949) 55°F 39°F (1948) October Normal Wettest Driest Precipitation 3.25 in. 13.20 in. (1985) 0.00 in. (1874)

10/19 in Mobile Area Weather History

In 2004 an evening storm produced an F0 tornado near Owassa in Conecuh County, AL where it downed several trees. (Data compiled from NWS Mobile, NWS Birmingham, newspaper articles, USA Archives and HurricaneCity.com)