By mattmantell on Wednesday, January 14, 2009 - 01:20 am: Edit Post
those of us who frequent your site are familiar with the best and most important way to judge a snowstorm, of course by that I mean the J.D.com snow-storm scale. That being said, I was curious as to how the folks over at the NWS determine the difference between potential winter storms. For instance, for parts of Ohio this evening, they are calling for 3-5 inches of snow, with winds and extreme cold. Extreme for Ohio that is. The NWS has issued a Winter Storm Warning. Now I KNOW that in the UP there is no WAY that this is going to be issued a "Winter Storm Warning" status by the NWS. This got a buddy and me discussing the topic.
So my question is, how does the NWS determine what a "WINTER STORM" is? It seems to me that it is on some sort of sliding scale? Or that it is up to the discretion of the branch office that issues the warning for a storm within its territory? Further more I am guessing that a "Winter Storm Warning" in the UP would also have to be a NON Lake Effect event? As this would be a "Lake Snow Warning". One more point that I have noticed, it seems to me that earlier in the season the NWS is a lot more likely to throw around "advisories", and "warnings" than they are later in the winter. For instance, tomorrow here in Ohio they are calling for 1-3" of snow in the PM hours. No advisories as of yet. If this "storm" was forecasted in October, November, or even possibly December, I guarantee there would be an advisory posted by the NWS and the salt truck would already be pre-treating the roads! JOHN, PLEASE SHED SOME LIGHT ON THIS CONFUSING SUBJECT!!!
By admin on Wednesday, January 14, 2009 - 09:44 am: Edit Post
Each NWS Forecast Office has it's own set of guidelines for weather advisories/warnings.
The general rule is that an advisory is issued when the weather will provide a hinderance to daily life like travel or being outside. A warning is issued when the weather will become potentially dangerous to travel or outdoor activity.
I also know that the NWS does take into consideration the public perception and experience with the conditions, meaning at the beginning of the winter season, they are more likely to issue an advisory or warning because the general public has not yet been seasoned to winter driving or winter weather in general.
By chords on Wednesday, January 14, 2009 - 10:22 am: Edit Post
Here are links that explain the criteria used to issue various watches,warnings ect..
By regionrat on Wednesday, January 14, 2009 - 11:43 am: Edit Post
A follow up question, if I may? Does the NWS err to the side of caution in regards to issuing advisories? Would they rather miss a bit on the forecast to better protect the welfare of the popluation?
By mattmantell on Wednesday, January 14, 2009 - 01:23 pm: Edit Post
Hey thanks for your time guys. That is basically what I figured, but never knew for sure. I like Ohio's criteria "AT LEAST 4 INCHES IN ABOUT 12 HOURS. UNDER CERTAIN CONDITIONS...HEAVY SNOW" HA! John you guys would be under a heavy snow warning from a November till April! It's frustrating sometimes when 6" of snow gets people worked into a panic! I must have been a yooper in a former life! Thanks again!
By admin on Wednesday, January 14, 2009 - 04:44 pm: Edit Post
I do believe they will error to the side of caution.
By alex2929 on Wednesday, January 14, 2009 - 05:22 pm: Edit Post
They deffinately can be too cautious. I sometimes think they throw the warnings too much in ohio where i live and people don't take them serious. It is amaizing to see how people react in the UP to snow versus at home. It is actually kind of funny sometimes.