Severe WX Severe Weather Threat 3/14-3/16

[jiharris0220]

The hrrr has the most realistic depiction of the storm mode on Saturday, it’s in between the fv3 fully discrete mode dooms day scenario and the NAMs linear qlcs system.

The dry line has a semi discrete to linear storm mode and the OWS has a fully discrete mode. And as expected, the UH tracks also fall in between the fv3 and Nam in severity.

 

[Cyclonic Paracosm]

The hrrr has the most realistic depiction of the storm mode on Saturday, it’s in between the fv3 fully discrete mode dooms day scenario and the NAMs linear qlcs system.

The dry line has a semi discrete to linear storm mode and the OWS has a fully discrete mode. And as expected, the UH tracks also fall in between the fv3 and Nam in severity.

hrrr has over-convection bias when it first gets to an event, next few runs should fix that and paint us an even better picture

 

[UpperLevelLOL]

HRRR wants to murder mississippi

....let's not with this kind of language

 

[malak1984]

That HRRR is not great for parts of East TN/N. GA and Eastern AL signs of early onset of some storms well before original timing. They will be strong lines of storms in those areas earlier then expected if pans out.

 

[NorthBamaWX]

They have canceled the Huntsville St. Patty Day celebration

 

[treypops]

The hrrr has the most realistic depiction of the storm mode on Saturday, it’s in between the fv3 fully discrete mode dooms day scenario and the NAMs linear qlcs system.

The dry line has a semi discrete to linear storm mode and the OWS has a fully discrete mode. And as expected, the UH tracks also fall in between the fv3 and Nam in severity.

I'd expect it to moderate some in subsequent runs.

 

[tornado examiner]

....let's not with this kind of language

Okay

 

[jiharris0220]

hrrr has over-convection bias when it first gets to an event, next few runs should fix that and paint us an even better picture

The hrrr does not have an over convection bias, in fact, it tends to over mix surface dews which actually leads to lower instability and therefore sometimes under does convection.

However, in this case, its depiction of the dry line and open warm sector looks accurate so far given the setup.

 

[Maxis_s]

James Spann saying that this will probably be upgraded to high risk, and that this is an event that happens "once every few years". Wow.

 

[UpperLevelLOL]

Yeah... "interesting"

 

[KAC11]

They have canceled the Huntsville St. Patty Day celebration

Same in Mobile...

 

[treypops]

James Spann saying that this will probably be upgraded to high risk, and that this is an event that happens "once every few years". Wow.

That will get your attention

 

[ColdFront]

Yeah... "interesting"

You have an entire OWS deep into Alabama too. I almost wouldn’t doubt any boundaries laid down or smaller confluence bands don’t fire off at least 2-3 cells out there. (Like the Cullman EF4)

It’s going to be really hard for some of the models to resolve that because the forcing mechanism is so subtle

 

[Anti Marine Layer]

Could any NCAA games get cancelled?

 

[Cyclonic Paracosm]

hrrr does sometimes show slop on its firs run of a event, next run should fix that, been told that from several people. but even then that run was insane

 

[joshoctober16]

I really don’t know if this is the place for this right now

i mean ... kind of dont know my self , i dont really think there is a composite debate thread.

also here is the STP map from HRRR

very wide 3+ STP

 

[Darklordsuperstorm]

Another snippet from the Spann video update: "With STP values like this we have to be concerned about a few long track violent tornadoes. I don't like to throw that term around unless we really mean it, but we really mean it."

 

[jiharris0220]

You have an entire OWS deep into Alabama too. I almost wouldn’t doubt any boundaries laid down or smaller confluence bands don’t fire off at least 2-3 cells out there. (Like the Cullman EF4)

It’s going to be really hard for some of the models to resolve that because the forcing mechanism is so subtle

You can see every cam attempting to convect the confluence bands in the OWS, some like the FV3 and Hrrr successfully do so while others like the NAM struggle to initiate anything.

In reality with the LLJ being as potent as it is and the abundant surface cape plus high lapse rates it’s hard to see how OWS supercells don’t occur.

 

[Grand Poo Bah]

HRRR showing the lowest dewpoints in Iowa, Missouri, and Illinois of all the CAMs

i mean ... kind of dont know my self , i dont really think there is a composite debate thread.

Probably a great topic for the Severe Weather Megathread once this is over.

 

[TornadoFan]