Feb 24-25th Event -- Generators for some, pre-emerg for others

[anthonyweather]

Wouldn’t be Suprised to see ice storm warnings up this way 

[penndotguy]

28 minutes ago, anthonyweather said:

Wouldn’t be Suprised to see ice storm warnings up this way 

Was thinking the same thing, probably tomorrow am

[anthonyweather]

wow cmc… 

[Hurricane Agnes]

12z 3k NAM in range (12z EC just started).

[Hurricane Agnes]

12z 3k NAM by ptype.

[Albedoman]

1 hour ago, Hurricane Agnes said:

 

 

 

Here is a link to Mt. Holly's Winter Weather Criteria for Warnings/Advisories (the page uses a mouse-over feature to show the regions and it will display the criteria legends at the bottom but I snap-shotted them to make it easier) - https://www.weather.gov/phi/criteria-winter

Each region within the CWA has different criteria for what triggers use of each product.

the main problem , the criteria does not at all match the physical geography of PA, especially for the Lehigh and Northampton Counties.  Weather is greatly dependent on physical geography, not the placement of interstates locations. Furthermore, It appears the Fall line is not in agreement with all criteria shown above. The warning criteria should have been set by the physical geographical feature of the Blue Mountains and not  the Fall line since many of the specifications concerning satisfying the criteria of winter warnings and watches are very elevation driven and dependent too.

Also, many readers of the discussion do not even know where the exact location of the Fall line actually is when mentioned in the discussion.  My main gripe is that the winter storm watch/warning  criteria for five inches is way too high for the LV which is the fastest growing area of state and as we are no longer rural.  Four inches should be the level as that is when the municipal snow plows usually drop the blade and plow as well. The winter weather criteria should have been simply set at the Blue Mts.  For the non- believers try going through the Lehigh Tunnel after  a usual winter storm event - Snow heaven on the north side, brown grass on the Lehigh/Northampton county south side. Based on this weather pattern we are in, Mt Holly needs to revisit the criteria this summer and change it to a realistic determination, especially for elevation driven winter storm events. Consistency must be utilized if you are going to have a productive warning system in place. Right now, utilizing point forecasts as their driver seat is not working well in these type of weather forecast especially when frozen precip is  ingested into the models that are fluctuating as much as they are today, its better to err and issue a winter storm watch.  Using confidence levels is not forecasting IMHO, its simple gambling and utilizing computerized weather forecasts which are becoming the rule  rather than based on true empirical science data, including physical geography.  

 

[RedSky]

ECM lost some precipitation this run but still cold with ice

 

 

[ChescoWx]

If the below as depicted by the Euro was close to reality....that would be an ice storm warning...but I am not biting

[anthonyweather]

10 minutes ago, ChescoWx said:

If the below as depicted by the Euro was close to reality....that would be an ice storm warning...but I am not biting

Just riding the NAM home?

[MGorse]

Some of these comments…oh my. 

[Hurricane Agnes]

Quote

the main problem , the criteria does not at all match the physical geography of PA, especially for the Lehigh and Northampton Counties.  Weather is greatly dependent on physical geography, not the placement of interstates locations. Furthermore, It appears the Fall line is not in agreement with all criteria shown above. The warning criteria should have been set by the physical geographical feature of the Blue Mountains and not  the Fall line since many of the specifications concerning satisfying the criteria of winter warnings and watches are very elevation driven and dependent too.

Well remember too that the interstates (and roads in general) were built to deal with that actual geography (or better, "topography") of the land, so you will see roads that are actually running along natural dips between hills.  I live in a hilly area myself and see that, especially because where I am is where the Piedmont begins.  The roads will also follow along creeks and rivers.  And thus you have I-95 that is running right along the fall line!  There was kindof a cool little blog article that I found that sortof talks about that - https://www.lastwordonnothing.com/2018/02/15/following-the-fall-line/

If you look at the criteria, it's not solely dividing along the N/S fall line, which essentially separates the flat coastal plain of NJ from areas west, but they also subdivide by latitude as well. And the interesting issue of the mountains that run across PA, is that the chains run SW to NE on a diagonal, so where they bisect land areas, will have an impact differently vs based solely on latitude.

But it would be near impossible to try to micro-tailor the Warnings/Advisories based on climatology down to the degree that you want to see (at least at the moment).  I think it was only recently when they were able to actually do "parallelogram" designations of smaller areas (vs county-wide) for the products they issue (notably important for the Warning products like FFW/TOR/TORE, etc).

Quote

Also, many readers of the discussion do not even know where the exact location of the Fall line actually is when mentioned in the discussion.  My main gripe is that the winter storm watch/warning  criteria for five inches is way too high for the LV which is the fastest growing area of state and as we are no longer rural.  Four inches should be the level as that is when the municipal snow plows usually drop the blade and plow as well. The winter weather criteria should have been simply set at the Blue Mts.  For the non- believers try going through the Lehigh Tunnel after  a usual winter storm event - Snow heaven on the north side, brown grass on the Lehigh/Northampton county south side. Based on this weather pattern we are in, Mt Holly needs to revisit the criteria this summer and change it to a realistic determination, especially for elevation driven winter storm events. Consistency must be utilized if you are going to have a productive warning system in place. Right now, utilizing point forecasts as their driver seat is not working well in these type of weather forecast especially when frozen precip is  ingested into the models that are fluctuating as much as they are today, its better to err and issue a winter storm watch.  Using confidence levels is not forecasting IMHO, its simple gambling and utilizing computerized weather forecasts which are becoming the rule  rather than based on true empirical science data, including physical geography.  

I know the Warning/Advisory criteria have changed over the years and gets tied to area impact. Where I am here in Philly in Chestnut Hill, I know we had a handful of local mets (broadcast ones, the few who were actually mets) who were familiar with hyper-local conditions including northwest Philly.  So for example, someone like Elliot Abrams (who many on here know about, who was a co-founder of Accuweather) went to school a few miles from where I live. Similarly, Hurricane Schwartz went to high school here in the city at a school about 5 miles from me (and a block from where I went to HS).  So whenever there were local forecasts, those local mets who were actually from here, would take the NWS info as supplementary guidance and would then tailor it to the locale.  They knew, for example, that here in the higher elevations of the city, the temps ran several degrees cooler than downtown and we often got more snow here because of that, so adjustments were always made. 

So remember that they are not just forecasting for up there or for down here but across parts of PA, NJ, all of DE, and parts of MD.

[MGorse]

The warning and advisory criteria is by zones not mountain ranges and such. The criteria is also run by each county Emergency Manager. We try to factor in many things when deciding where to issue a watch. We did not purposely leave out Lehigh County, but focused where the higher snow/sleet is forecast plus where the higher confidence was. We have to start somewhere. Look for additional forecast updates later this afternoon and again tonight. We try our best and we are certainly not perfect! 

[Ralph Wiggum]

3 minutes ago, MGorse said:

The warning and advisory criteria is by zones not mountain ranges and such. The criteria is also run by each county Emergency Manager. We try to factor in many things when deciding where to issue a watch. We did not purposely leave out Lehigh County, but focused where the higher snow/sleet is forecast plus where the higher confidence was. We have to start somewhere. Look for additional forecast updates later this afternoon and again tonight. We try our best and we are certainly not perfect! 

You guys at Mt Holly are tops in the biz... not even close. Probably the most diverse region in the US to forecast for. Majority of us truly appreciate what you folks do over at the NWS. Thank you!

[MGorse]

2 minutes ago, Ralph Wiggum said:

You guys at Mt Holly are tops in the biz... not even close. Probably the most diverse region in the US to forecast for. Majority of us truly appreciate what you folks do over at the NWS. Thank you!

Thank you for the kind words and understanding. 

[anthonyweather]

I wouldn’t be Surprised to see ice storm warnings for Lehigh and poconos, surely models are showing the criteria being met

[Rockem_sockem_connection]

I picked up some pre emergent for the lawn today but I'm not sure when it'll go down. Whenever temps are regularly in 50s and below freezing stops. Doesn't look like it's happening in the immediate future

[Hurricane Agnes]

12z EC tries to fade a dryslot in with lesser precip to sortof look like the NAM.  

[MGorse]

10 minutes ago, anthonyweather said:

I wouldn’t be Surprised to see ice storm warnings for Lehigh and poconos, surely models are showing the criteria being met

Perhaps but a challenge given the recent warmth. I could see more sleet occurring over snow. 

[Hurricane Agnes]

18 minutes ago, MGorse said:

The warning and advisory criteria is by zones not mountain ranges and such. The criteria is also run by each county Emergency Manager. We try to factor in many things when deciding where to issue a watch. We did not purposely leave out Lehigh County, but focused where the higher snow/sleet is forecast plus where the higher confidence was. We have to start somewhere. Look for additional forecast updates later this afternoon and again tonight. We try our best and we are certainly not perfect! 

There is no way you can do "hyper-local" forecasting (at least with the tech that is available today) and even then, it would be TMI for the average person.

Keep up the good work!

[MGorse]

Just now, Hurricane Agnes said:

There is no way you can do "hyper-local" forecasting (at least with the tech that is available today) and even then, it would be TMI for the average person.

Keep up the good work!

Yup especially with watches, warnings and advisories. Appreciate it! 

[Hurricane Agnes]

I think the front has been moving through now. The winds have picked up significantly in the last 30 minutes or so. So far I hit 68 for a high and am bopping between 67/68 but the dp has taken a big hit and is now down to 46.

[Hurricane Agnes]

1 minute ago, MGorse said:

Yup especially with watches, warnings and advisories. Appreciate it! 

I'm just amazed at the little flood warnings that will run right along the sides of a river, which can be a tiny area on a map compared to the Warning areas for other products.  That's probably about as hyper-local as I have seen.

[MGorse]

6 minutes ago, Hurricane Agnes said:

I'm just amazed at the little flood warnings that will run right along the sides of a river, which can be a tiny area on a map compared to the Warning areas for other products.  That's probably about as hyper-local as I have seen.

Yeah those are different and based on known impacts tied to a river gage level. 

[MGorse]

12 minutes ago, Hurricane Agnes said:

I think the front has been moving through now. The winds have picked up significantly in the last 30 minutes or so. So far I hit 68 for a high and am bopping between 67/68 but the dp has taken a big hit and is now down to 46.

Great observation! Dew points will be first to really drop with the frontal passage. Main cold air push is during tonight. 

[Hurricane Agnes]

Just now, MGorse said:

Great observation! Dew points will be first to really drop with the frontal passage. Main cold air push is during tonight. 

It got threateningly dark here at the time too - like an attempt at a gust front (but a bit disorganized). However it has since cleared out with blue sky dotted with some cumulus.

[ChescoWx]

1 hour ago, Ralph Wiggum said:

You guys at Mt Holly are tops in the biz... not even close. Probably the most diverse region in the US to forecast for. Majority of us truly appreciate what you folks do over at the NWS. Thank you!

Agreed 100% our Mt. Holly team is tops!! - folks like me can look at maps till they are blue in the face....but the 1st place I go for the real forecast is NWS Mt. Holly.....all the models we post are simple guidance for the professionals like Mike and the Team to take into account when they make a professional forecast.

[Lady Di]

Bunch of Watches, advisories, and statements are out. It pretty much covers all you folks up north.

Hoping we do OK down here. I have a procedure scheduled on Friday-will see what happens with it.

[Albedoman]

1 hour ago, MGorse said:

The warning and advisory criteria is by zones not mountain ranges and such. The criteria is also run by each county Emergency Manager. We try to factor in many things when deciding where to issue a watch. We did not purposely leave out Lehigh County, but focused where the higher snow/sleet is forecast plus where the higher confidence was. We have to start somewhere. Look for additional forecast updates later this afternoon and again tonight. We try our best and we are certainly not perfect! 

thanks Mike. But the key here is the term "zones". Zones should be based on physical topographical delinations, not just by county lines or interstate highways. Since the late 80's - early 1990's the NWS started going from the airport offices and went to a regional based approached. I was one of the naysayers back then stated that regionalization of the NWS loses  a much needed  local perspective of topographical weather issues and places much more emphasis on computer modelogy and not the physical geography characteristics of the ridge and valley region of eastern PA, especially the LV. I really also  do not like the idea of a county Emergency Manager setting the storm criteria as the they have no control of the federal and state highway system, PADOT does. Rt 22, Rt 309, Rt 100,  Rt 33  and I-78 are  the lifeline for the entire  trucking industry and the LV residents in PA and I believe PADOT should have a say so at the table too. 

Cyrious, does each of the zones in Eastern PA  being defined by physical geography or just political boundaries? How are these zones formed and what is the basis of each of these zones when assigning criteria for warnings and watches?  That has never been really explained to me if you have the time?  

Again, Thank you for issuing the winter storm watch for Lehigh County by the way.

[Newman]

Mount Holly ice forecast and 18z RGEM below. Definitely not going to see 1" of ice like the RGEM, but parts of the Lehigh Valley could definitely see up to, or perhaps over, 0.5" of ice. I still think sleet will keep accretion down

[MGorse]

54 minutes ago, Albedoman said:

thanks Mike. But the key here is the term "zones". Zones should be based on physical topographical delinations, not just by county lines or interstate highways. Since the late 80's - early 1990's the NWS started going from the airport offices and went to a regional based approached. I was one of the naysayers back then stated that regionalization of the NWS loses  a much needed  local perspective of topographical weather issues and places much more emphasis on computer modelogy and not the physical geography characteristics of the ridge and valley region of eastern PA, especially the LV. I really also  do not like the idea of a county Emergency Manager setting the storm criteria as the they have no control of the federal and state highway system, PADOT does. Rt 22, Rt 309, Rt 100,  Rt 33  and I-78 are  the lifeline for the entire  trucking industry and the LV residents in PA and I believe PADOT should have a say so at the table too. 

Cyrious, does each of the zones in Eastern PA  being defined by physical geography or just political boundaries? How are these zones formed and what is the basis of each of these zones when assigning criteria for warnings and watches?  That has never been really explained to me if you have the time?  

Again, Thank you for issuing the winter storm watch for Lehigh County by the way.

Zones overall match the county borders. There are some exceptions like Bucks, Montgomery and Chester counties which were split years ago to better define the more urban from the higher elevation areas. Splitting of counties/zones is a long process. 
 

Emergency Managers do no set the criteria. They review what is planned to be in place basically to provide feedback. The criteria is based in part on climatology. PennDOT is usually not involved because the criteria is not strictly for what accumulates on roads. That is very difficult to predict. Some adjustments for as least some areas to the warning/advisory criteria were made over the years. There is some wiggle room when it comes to winter storm warnings as combined impacts can be taken into account despite the individual snow and ice amounts being below warning criteria. 
 

Lastly, I had no hand in expanding the winter storm watch this afternoon.