brianc33710

Delta is forecast to go over the Yucatan Peninsula & reemerge over the south central Gulf. Then it's forecast to go toward the LA coastline Fri pm/Sat am. The cooler water & increased shear should weaken Delta some before the north Gulf landfall. But the strength at its peak will still determine its strength at its final landfall.

Wow! Even tropical storm force winds extend no further than 90 mi from Delta's center! Hurricane force is only 40 mi from the eye. EDIT: Gilbert hit Cancun as Cat 5 in September 1988 & had a tiny eye too. I'm not saying that Delta will reach 185 mph with a 888 mb pressure, but there are obviously some similarities.

I think that Sally being the first hurricane to affect the Mobile-Pensacola area since we sold our condo almost 2 years ago counts as "banter." My mom is sleeping more soundly than she would otherwise.

This is part of the MS "Pine Belt."

Purvis 10 min from the tornados path. Hattiesburg, w/ 46 k, isn't that far from its track.

Why isn't there still at least some daylight near that cell? TWC has the feed, and its very dark there.

Well, BMX has now pushed the 5 zones further south. Hamilton, Cullman & Gadsden has no risk at all. Jasper, Birmingham proper & Anniston are marginal. But the southern tip of Jefferson Co, most of Shelby Co, Tuscaloosa & Sylacauga are labeled slight. From Eutaw to Clanton to Alexander City is enhanced. And Demopolis, Selma, Montgomery & Auburn are still moderate. I guess we will just get everyday storms with a ton of rain, but that could cause flooding problems on its own.

SPC/BMX has Bham in a slight risk. Not far north is only marginal, while not too far south is enhanced. I guess they're just waiting to see where the models take the low. I think that the slight risk means that the warm front makes it to about I-20. The airmass won't be as cold & dry as Easter morning but still not conducive as needed for a significant outbreak. So, we need warm air invection, but not as much. But, we probably won't get as much as what came thru Easter either. If later models move the low north, then the risks will shift with it. S AL could wind up with what weather they feared last Sunday but didn't get.

I haven't been able to keep up today. Did the SPC expand the moderate risk N & E? Much of what happened later was in the "enhanced" risk.

The SPC was right to NOT upgrade this outbreak to a high risk. This was a significant severe weather outbreak, but moderate risk much better summarizes what did & didn't happen. The 1st PDS TW was right but the 2nd didn't really reach the criteria. We had an EF-4/5, and we don't yet know the number of EF-2/3s. And of course we had some EF-0/1s. I guess we will find out more over the next 2-3 days. I know it's not 100% over. I just want to qualify what I wrote.

Yeah, the supercell started in MS and held together all the way until the 4000+ ft mtns in NC finally tore it apart, over 8 hrs & can't remember how many 100s miles.

Yeah. The PDS TW 110 had some strange probabilities. The SPC gave a 90% chance for wind damage but just 10% for 65+ kts. We had non-tornado winds up to 80.

Right now things are quieter than I had thought this time yesterday. The night is still fairly young though.

OK. 2 pm Montgomery is now 81/70 & Jackson 81/69. Tuscaloosa 69/64, Bham 66/62, Calera 67/53.

145 PM CDT SUN APR 12 2020 AREAS AFFECTED...NORTHERN AND CENTRAL ALABAMA AND FAR SOUTHERN MIDDLE TENNESSEE. CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY VALID 121845Z - 122015Z PROBABILITY OF WATCH ISSUANCE...95 PERCENT SUMMARY...THE SEVERE WEATHER THREAT CURRENTLY OVER MISSISSIPPI WILL SHIFT EAST INTO ALABAMA LATER THIS AFTERNOON. A DOWNSTREAM TORNADO WATCH WILL BE NEEDED SOON. DISCUSSION...A MCS MOVED ACROSS NORTHERN LOUISIANA THIS MORNING AND PRODUCED NUMEROUS TDS SIGNATURES. THIS SAME CLUSTER OF STORMS HAS PRODUCED A TDS MORE RECENTLY (~1830Z) IN WEST-CENTRAL MISSISSIPPI. THIS SAME LINE OF STORMS IS EXPECTED TO MOVE EAST NORTHEASTWARD INTO NORTHERN ALABAMA LATER THIS AFTERNOON AND INTO THE EVENING. THE AIRMASS ACROSS NORTHERN ALABAMA HAS DESTABILIZED ACROSS THE LAST SEVERAL HOURS AND CONTINUED MOISTENING/WARMING IS EXPECTED AS THE WARM FRONT LIFTS NORTH. THEREFORE, THIS ONGOING MCS IS EXPECTED TO MAINTAIN ITS CURRENT INTENSITY AND LIKELY STRENGTHEN FURTHER AS IT MOVES INTO ALABAMA. A 997MB MESO-LOW HAS FORMED IN SOUTHEAST AR/WESTERN MS. THIS HAS ACTED TO LOCALLY ENHANCE THE BACKING OF SURFACE WINDS AHEAD OF THESE STORMS. THIS HAS LED TO VERY LARGE 0-1 SRH VALUES NEAR 700 M2/S2 PER GWX VWP. DAMAGING WINDS AND QLCS TORNADOES WILL CONTINUE TO BE A THREAT WITH THIS MCS AS STORMS MOVE EASTWARD. HOWEVER, THERE IS A CONDITIONAL THREAT FOR SURFACE BASED SUPERCELLS TO DEVELOP SOUTH OF THIS ACTIVITY IN THE WARM SECTOR. IF THIS OCCURS, A SIGNIFICANT, THREAT WOULD BECOME MORE LIKELY. A TORNADO WATCH WILL BE NEEDED SOON EAST OF THE CURRENT WATCH IN MISSISSIPPI.

OK. At 1 pm, Demopolis was 76/69 & Tuscaloosa 64/60. The front is on the move north. 2 PM is right around the corner.

Did this image come through for anyone else?

I found this regarding the SPC's delay with not going high risk, so far: SPC: THERE IS STILL ENOUGH UNCERTAINTY WITH REGARD TO CONVECTION OUTPACING STRONGER SURFACE-BASED INSTABILITY (ESPECIALLY WITH NORTHEAST EXTENT), AS WELL AS THE OVERALL CONVECTIVE MODE, TO PRECLUDE AN UPGRADE TO HIGH RISK.

Yes, I have also seen that text considering an upgrade. After the confection clears and the warm front moves through, I guess they want to see how quickly the area. Here is their wording: SPC: THERE IS STILL ENOUGH UNCERTAINTY WITH REGARD TO CONVECTION OUTPACING STRONGER SURFACE-BASED INSTABILITY (ESPECIALLY WITH NORTHEAST EXTENT), AS WELL AS THE OVERALL CONVECTIVE MODE, TO PRECLUDE AN UPGRADE TO HIGH RISK.

The Day 1 SPC outlook is out. They spread MOD further east, but doesn't upgrade any of the area to High. They didn't even mention potentially pulling the High Risk trigger later today. Everything looks like it's there, but they didn't include any upgrade wording.

Where is the warm front now?

This is my take, for what its worth. Right now the dewpoint in Bham is 34. The highest dp in central AL is just 41. Yes, I know that the warm front comes thru tonight, but the of-needed 80 deg his, not just the 70 dps, are S of a line from Demopolis to Auburn. And the best dynamics are N of that line. Right now, I'm skeptical, and will go with a squall line like type of event. Feel free to disagree though. Also, Broyles, who took the bold move of inserting the 45% contour inside the already HIGH risk 9 yrs ago, seems less than convinced for Sunday. Things can change though, and that would prove me wrong.

I can't share the new Day 2 outlook for Sunday. But, the only real expansion by the SPC is the enhanced level stretched into KY. While I did expect them to broaden the MOD to include more of AL & into TN, the delay in pulling the High Risk lever doesn't surprise me.

Two things for discussion: James Spann actually thinks that the SPC will go with the High Risk next update, which seems a little too soon. But he has 40 + years of experience so I will defer to him. Also, is the Nashville, TN EF-4 the only violent tornado so far in 2020? I know that they also had an EF-3, but their NWS office did find some EF-4 damage.