NavarreDon

NHC track has been shifting east all day. The new forecast track is nudged a bit to the east of the previous track during the first 36 h based on the initial position, and it lies just to the west of the consensus models. One uncertainty in the track forecast is the possibility that the center could re-form to the north, which at the least could change the timing of the forecast track. And then there’s this, The dynamical models forecast Alberto to reach an area of stronger upper-level divergence in about 24 h, with the models agreeing on more significant development starting about that time. The intensity forecast shows a slower development rate for the first 24 h than the previous forecast, then shows a faster development to the 55-kt peak intensity of the previous forecast. After landfall, Alberto should quickly weaken over land. The new intensity forecast is near the intensity consensus and the SHIPS model. Some of the intensity guidance suggests that Alberto could become a hurricane before landfall. If the guidance trends stronger, a hurricane watch could be needed for a portion of the Gulf Coast on Saturday

Here is a what MOB thinks of the potential hydro impacts. Flash Flood Watch may need to be expanded northward. In general, storm total rainfall amounts of 6 to 12 inches, with locally higher amounts of 12 to 15 inches, are possible roughly over the southern portion of the area .

MOB raising some eyebrows over this system. SHORT TERM /Wednesday night Through Friday night/...An upper ridge weakens while slowly shifting eastward across the eastern states to the east coast through Friday night as an upper trof advances from the northern/central Plains and begins to move into the eastern states. This transition is of importance as it influences a weak upper trof which initially exists from the Sabine River valley into the northwest Gulf and results in this weak trof becoming somewhat better defined while shifting slowly eastward to the north central Gulf and southern Mississippi River valley. The ramifications of the position of this upper trof will be to play a big role in the movement of a surface low expected to develop over the south central or southeast Gulf, and favor a general northward movement of this potential feature. Development of the surface low looks probable, so the big questions are when and where the system develops. As noted earlier the upper trof will likely favor a northward movement with this system, but depending on where it develops (south central or southeast Gulf), this will determine if the surface low moves towards the north central or the northeast Gulf. There are some environmental limitations on this potential system, such as somewhat drier air noted in the water vapor loop over the Gulf, but the configuration of the surface low will likely be tropical (warm-core). The National Hurricane Center currently has a 40% chance for tropical cyclone development over the eastern or central Gulf during the period, and will continue to monitor this as closely as possible. While there are uncertainties with timing and movement of the anticipated surface low, confidence is increasing for very high pops as well as for potential flooding threats. Following upon guidance and WPC QPF amounts, have issued a Flood Threat graphic which will begin from late Thursday and continue through late Sunday (the LONG TERM period). Have gone with a Significant Threat Area generally south of Highway 84 where areas of flash flooding will be possible and an Elevated Threat Area further to the north where isolated to areas of flash flooding will be possible. Heavy surf is likely along with a moderate risk of rip currents through Friday then likely becoming high by Friday night. At least minor coastal flooding could begin as early as late Thursday, with the potential for coastal flooding impacts increasing through Friday night. /29 LONG TERM /Saturday Through Tuesday/...The forecast depends entirely on the timing and movement of the anticipated Gulf system. Should this system materialize as anticipated, a movement to the north central or northeast Gulf coast looks most likely based on the influence of the upper trof as alluded to in the SHORT TERM section. A plausible solution (from a consensus of guidance) has the system moving to the north central/northeast Gulf coast in the Saturday into Sunday night timeframe. As mentioned earlier, the National Hurricane Center has a 40% chance for tropical cyclone development with this system and will closely monitor. It is too early to be able to assess potential wind impacts, but confidence has increased for flooding potential and a Significant to Elevated Threat of flooding follows through at least Sunday. In addition, the pattern supports likely to categorical pops through most of the period. A high risk of rip currents and heavy surf is likely through at least the weekend along with coastal flooding impacts. May also need to assess the potential for severe (tornadic) storm development, but unable to delve into any specifics right now as this will depend heavily on the timing/movement of the system. /29

Special Tropical Weather Outlook NWS National Hurricane Center Miami FL 730 PM EDT Mon May 21 2018 For the North Atlantic...Caribbean Sea and the Gulf of Mexico: 1. A broad surface low pressure area has formed over the northwestern Caribbean Sea a couple of hundred miles east of the coast of Belize. This low and an upper-level trough are producing widespread cloudiness and showers extending from the northwestern Caribbean Sea across Cuba and the Florida peninsula. While environmental conditions are expected to be unfavorable for development during the next couple of days, some gradual subtropical or tropical development is possible later this week while the system moves slowly northward into the central or eastern Gulf of Mexico. Regardless of development, locally heavy rainfall is possible across western Cuba and much of Florida during the next several days. For more information on the heavy rain threat, please see products issued by your local weather office. The next Special Tropical Weather Outlook on this system will be issued by 800 AM EDT on Tuesday. * Formation chance through 48 hours...low...near 0 percent. * Formation chance through 5 days...medium...40 percent. Forecaster Cangialosi

Will be keeping an eye on this from the Western FL Panhandle. Looks like at a minimum Memorial day weekend could be a soggy one! MOB LT disco: .LONG TERM /Friday Through Monday/...The developing surface low pressure over the central Gulf could transition into a tropical, warm core system over the central Gulf by Friday and then likely drift north toward the central Gulf coastal region through the early part of the weekend, although a few model solutions keep it closer to the Florida peninsula. NHC is now indicating a 40 percent chance of a some gradual subtropical or tropical development later this week while the system moves slowly northward into the central or eastern Gulf of Mexico. There is still some uncertainty with the forecast movement and strength of this system as it moves generally north toward the northern Gulf coast. It is still too early to discuss any real specifics with this system, but the overall developing pattern does continue to support at least likely PoPs across most of the Gulf coast region through the period. Depending on the evolution of the system other impacts such as potential flash flood concerns, as well some marine hazards such as minor coastal flooding and high surf and increased rip current risk along area beaches may have to be addressed as well. We will continue to monitor this situation. Little change in temperatures is expected in the long term, although daytime highs could be a little lower by the weekend due to extensive cloud cover and precipitation. 12/DS

Just wanted to stop by and wish you all a very Merry Christmas! Hope it’s a great one for all of you. Please keep those that are less fortunate & those serving our country in your thoughts this holiday season. Thanks for letting this beachcomber invade your thread every so often so I can feed my snow addiction. Bless you all!!! .

So, what were some totals from the NWFS portion of the event?

Just saw the UNCA weather tweet and it had a parking lot video. Completely ripping and windy. The camera at Wolf Ridge has been obscured by snow. One for the ages for you folks!!!

These pics are from northern Escambia county (North of Pensacola). Reports of 2" in that area of the state!

Hope you guys don't mind if I post this here. If so I can move it to the regular obs thread. This was last night in Northern Escambia county (North of Pensacola). There are reports of 2" up that way!

Simply amazing, did some poking around and found out that the area averages snow once every 17 years! Now I'm not going to have to break out the shovel anytime soon but, there is something to be said about falling snow where it really shouldn't. Woke the wife up to witness it and you would think we were kids on Christmas morning! As always I'm happy for all of my WNC peeps for leading the way in the SE. If you're bummed about your totals just think about the Raleigh crew and what they had to go thru! Glad we all got to celebrate snow for this one. Heard on TWC that all 50 states have had at least a trace of snow in 2017.

And it’s snowing at the Beach! Panhandle snow paradise...LOL! .

Sorry for the Raleigh peeps! Mobile AL has recorded snow tonight. It’s the earliest in their 175 years of record keeping. .

You can clearly see the snow intensifying in AL and making it’s way towards WNC. How can he say anything other than more snow is likely tonight! .

The weather underground show on The Weather Channel is going nuts about the Mnts in WNC! Just said a Maggie Valley report with 12”! They are also on the bandwagon for tonight! .