How does this happen?

[Todd Lemery]

I live in the purple shaded advisory area surrounded by a sea of blue. This is a pretty frequent occurrence for my county and wonder how this happens? I’m pretty sure I don’t live in a bubble and realize that there is a different forecast office for Michigan and Wisconsin. But really? I tried to post a screen shot of a wider view, but couldn’t get it to upload. Most of Michigan lower peninsula is also blue.

 

[JamesCaruso]

Looks like what I have to deal with in southeast PA when an SPC risk or watch area stops just west of where I live, or an approaching squall line parts like the Red Sea on either side of me [emoji52][emoji57]

But seriously, the only thing I could possibly guess - and admittedly it seems unlikely - is that your elevation is lower than the surrounding area? My understanding is that just a few hundred feet can make a difference in accumulation and absent a large snowfall that could be pushing you just below warning criteria??

Does your local AFD shed any light on the rationale for this? If not, you might want to see if you can ask your local NWSFO, maybe via direct message on Twitter or Facebook. Does your local area have a weather forum of some sort? In the Philadelphia area we have a great one, PhillyWeather.net, which includes a great caliber of amateur meteorologists as well as current and retired folks from the local NWSFO.

 

[rdale]

James - there is no Winter Storm Warning anywhere. His county was upgrade to a Winter WEather Advisory for tonight, and then will match the other counties with a Winter Storm Watch for the weekend event. I think people are misinterpreting colors (we've strongly suggested for years that they drop to a 3 or 4-color system.)

 

[MWNault]

Hi James - as u probably remember hearing - each severe weather watch area states "persons in and close to the watch area should listen for later statements and possible warnings".

 

[Todd Lemery]

I guess, to clarify what I don’t understand, is how the conditions (or forecast conditions) are substantially different where I live than it is for at least a hundred miles in any direction. No matter which direction I go, I almost immediately would be in the watch area. Why would my county be singled out as the odd step child? Are these areas computer generated or are they hand selected by NWS employees? Or a combination of both?
I’m pretty sure James knows what a watch area is and possible upcoming changes to it. The question is how one county in the middle of a watch area is treated differently.
This sort of thing happens frequently in the county I reside.

 

[rdale]

MWNault - there was no severe weather watch.

Todd - all human generated. The meteorologist had a high level of confidence for the overnight period in your area that was not matched in other areas.

 

[S. Andrew Walters Jr]

haha, I see a lot of the watch/warning/advisory "doughnutting" around the OH Valley as well, could be differences in winter threat criteria thresholds for your county; e.g. Cincinnati has Winter Storm Warning criteria of 3-5" of snow, while across the river the Winter Storm Warnings are issued for 2-4" (I believe those are the correct values). Or as rdale pointed out, it is an Advisory for a previous threat and the Winter Storm Watch actually overlays it.