622 FXUS64 KMOB 110900 AFDMOB Area Forecast Discussion National Weather Service Mobile AL 400 AM CDT Thu Apr 11 2019 .NEAR TERM /Now Through Thursday night/...Short wave upper ridge axis was nosing northward from the Gulf up across Kentucky this AM while a potent storm system was lifting northeast over the central High Plains. Water vapor imagery indicates a large zone of dry air from off the southeast US coast westward to east TX. At the surface, high pressure has moved east of the area and a light south to southeast flow is now in place and will continue for the duration of the near term. For today, rain-free weather continues and with the high to the east, another warm day is expected with highs well above seasonal levels under a mix of sun and clouds. A few areas may see near record warmth for April 11th. Going into tonight, clouds are forecast to increase from west to east as a frontal boundary advances eastward to the TN Valley to central LA by daybreak Friday. Isolated showers (PoPs~20%) could break out over the northwest zones late tonight, generally west of a line from Thomasville AL to Lucedale MS. Elsewhere, PoPs are 10% or less. Have also mentioned late night patchy fog formation as the short range ensembles and the NAM12 suggest its formation generally along and east of I-65 with some eastward migration noted by sunrise Friday with approaching front. Overnight lows are favored to be well above seasonal normal, even more so. /10 .SHORT TERM /Friday Through Saturday night/...An occluded system well to the north will have brought a trailing cold front into the region at the beginning of the period, which extends from coastal Texas into central Tennessee. As an upper trof advances across the central states through Saturday night, a surface low develops over eastern Texas and moves to near the Mississippi/Ohio river confluence while the frontal boundary in the region moves well to the north as a warm front. In response to a series of shortwaves moving through the upper trof and warm air advection in the lower levels, a line of convection is expected to develop and advance to near the lower Mississippi river valley by early Saturday evening. The line of storms continues eastward and advances into the western portion of the forecast area late Saturday night. MLCAPE values will have increased to 500-1000 J/kg over much of the area on Saturday, and despite the nocturnal timing similar values continue over the area Saturday night. The 850 mb jet strengthens to near 50 knots Saturday night as well, resulting in 0-1 km helicity values of 200+ m2/s2. Sig Tor values up to 3 are expected Saturday night, and the environment indicates potential severe weather. In addition, expect high rain rates with the convection as very high precipitable water values near 2 inches will be present over the area. For Friday, will have slight chance to chance pops west of I-65 due to mainly modest isentropic lift then slight chance to chance pops follow for Saturday as isentropic lift increases somewhat. Pops increase dramatically Saturday night with likely to categorical pops for most of the area as the convective line advances into the area. Highs on Friday and Saturday will be mostly in the lower 80s. Lows Friday night range from the lower 60s inland to the mid 60s closer to the coast, then Saturday night will be rather mild with lows 65 to 70 expected for most of the area. A moderate risk of rip currents on Friday is expected to increase to high on Saturday. /29 .LONG TERM /Sunday Through Wednesday/...The upper trof takes on a negative tilt while continuing into the eastern states early in the period. The surface low moves from the Mississippi/Ohio river confluence into the northeast states and meanwhile brings a strong cold front through the forecast area on Sunday. A line of strong convection will be oriented north/south near the mid section of the forecast area early Sunday morning and continues eastward, possibly exiting the forecast area as early as midday Sunday. The convective line will be in an environment with MLCAPE values of 500-1000 J/kg and 0-1 km helicity values of 200+ m2/s2 along with Sig Tor values up to 3. As such, severe weather will be possible with the convective line along with high rain rates due to abundant deep layer moisture. Will have likely to categorical pops for much of the area Sunday morning (except lesser pops generally over southeast Mississippi), then pops decrease areawide to slight chance to good chance pops in the afternoon. Dry conditions follow for Sunday night into Tuesday night in the wake of this system, then expect a chance for rain to return on Wednesday ahead of another system advancing across the central states. A high risk of rip currents is expected to continue Sunday then the rip current risk tapers off. /29 && .MARINE...The next period of a ramp up in hazardous conditions for smaller marine craft comes into the weekend as a low pressure system evolving over TX on Saturday intensifies as it lifts northeast over the Mid-South during the early AM hours Sunday. Ahead of this system, onshore flow strengthens and the duration of the developing longer southerly fetch results in a marked build in seas. Small craft advisories will likely be required thru the weekend. There is also concerns that the passage of storms could be strong to perhaps locally severe by late Saturday night and continuing into Sunday AM. /10 && .PRELIMINARY POINT TEMPS/POPS... Mobile 82 64 83 65 80 66 75 44 / 0 10 10 10 30 100 60 0 Pensacola 80 67 81 67 80 70 77 48 / 0 10 10 10 20 70 90 10 Destin 78 67 79 67 79 70 74 53 / 0 10 10 10 20 40 90 10 Evergreen 86 61 84 62 84 68 75 43 / 0 10 10 10 20 70 90 10 Waynesboro 85 63 80 62 80 65 72 43 / 0 20 40 30 40 100 40 10 Camden 84 62 82 63 84 66 76 44 / 10 10 20 20 20 80 80 10 Crestview 85 60 84 61 84 66 77 45 / 10 10 10 10 20 50 90 10 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...None. FL...None. MS...None. GM...None. && $$ This product is also available on the web at: http://weather.gov/mob