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!

Some of these comments…oh my.

Sleet is included with snow regarding accumulations. Sleet can be messaged separately if significant but otherwise it is combined.

Interesting event. I recall at least some of the model guidance showing pronounced 700 mb or 850 mb FGEN farther northwest of I-95 and closer to the I-78 corridor, yet some were showing less snow. It is like what the model was showing at the surface was playing catch-up to the dynamics aloft. Colder air deeper farther west which placed that lift much better into the favored dendritic snow growth zone.

No I referenced New Castle County because that is farther southwest and had 3-6 inches. The 4-5 inch reports in Philadelphia County seen too low. As for that PNS, I am not sure why those old reports were added back in.

Thanks for asking.

There were several 3-6 inch reports in New Castle County, DE. Given that and some other reports in Philly, I would say 4 inches in south Philly is too low.

I feel like I am being interviewed. Lol. That statement sums it up well. Many times this is being said incorrectly because the energy is not being transferred. New coastal low develops due to incoming upper level support (results in surface pressure falls) while the inland low weakens then dissipates as the upper level support leaves it behind.

If we do not receive an updated report or final report then that is removed from the PNS. This is because it then becomes less representative. We do our best to quality control all reports but there are times when some slip through. If we catch it later then it is removed. We usually get tons of reports for snow events (overwhelming at times). Also, keep in mind that the airports that measure snow (PHL, ABE, ILG and ACY in our area) continue to measure and report every 6 hours.

I continue to post here from time to time, and yes I am still at NWS Mount Holly. The PHL measurement has not been taken in National Park, NJ in years. It is done at the airport. Airport’s are not the best places to measure snow but they do their best. As for snow ratios, we have in-house tools where we can blend different models to get the values desired. WPC also provides guidance on the ratios. Lots of internal collaboration occurs especially with big events like yesterday. We then use tools that take the forecast QPF and apply the selected ratios to give snowfall amounts. This can also account for temperatures as well. So in short, our forecast snowfall does account for ratios.

It is technically in Delaware County. We list it as in Philadelphia County though for continuity plus it represents Philadelphia.

According to his Facebook post a few hours ago, 6ABC has Philly in the 6-12 inch range (highest east into interior south NJ).

Not bad. Definitely overperformed.

I don't drink coffee, but maybe I should.

Oh it has been loads of fun!

PRE = Predecessor Rain Event

Those self checkouts and I do not always get along, especially at grocery stores!

When is he not doing that?!

That was just for you.

0.5-2 inches is bullish?

Rochester Airport reporting 2 inches in the last hour... KROC 171454Z 04019G27KT 1/4SM R04/1600V2600FT +SN FZFG BLSN VV006 M03/M04 A2912 RMK AO2 PK WND 04027/1454 SLP869 SNINCR 2/8 P0005 60010 T10281039 56012

Yup... KROC 171354Z 04015KT 1/4SM R04/2000V2800FT +SN FZFG BLSN VV005 M02/M03 A2913 RMK AO2 SLP873 P0004 T10221028

You know you want to.

It is quite amazing, but I like snow so it is rather frustrating as well.

Short staffed again but we are making it work. Amazing the arctic air in place now will be gone tonight with just a wind driven rain occurring.