Hurricane Agnes

My high for today likely will be the 57 at 2:40 am this morning and I finished up with 1.01" of rain yesterday with 0.48" this morning for a 2-day, 1.49" event total Currently overcast, breezy, and 47 with dp 46.

I blame RedSky for making me watch his chasers in FL & SC chasing Hurricane Ian. Looks like the coastal is pushing some heavier blobs up from the south. Am currently at 46 with dp 45 and very light rain with 0.68" for the event so far. The wind gusts continue to increase as well.

Mt. Holly tweeted a graphic model prediction of the temp drop to happen tomorrow (e.g., going from 42 to 15 in 12 hours) - Lots of hazard watches, advisories, warnings up now (including a Wind Chill Advisory & a Wind Advisory for much of the CWA) - Wind Chill Advisory URGENT - WINTER WEATHER MESSAGE National Weather Service Mount Holly NJ 258 PM EST Thu Dec 22 2022 DEZ001>004-MDZ012-015-019-020-NJZ009-010-012>027-PAZ070-071- 101>106-230900- /O.NEW.KPHI.WC.Y.0003.221223T2300Z-221224T1500Z/ New Castle-Kent-Inland Sussex-Delaware Beaches-Kent MD- Queen Annes-Talbot-Caroline-Hunterdon-Somerset-Middlesex- Western Monmouth-Eastern Monmouth-Mercer-Salem-Gloucester-Camden- Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May- Atlantic Coastal Cape May-Coastal Atlantic-Coastal Ocean- Southeastern Burlington-Delaware-Philadelphia-Western Chester- Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks- Lower Bucks- Including the cities of Wilmington, Dover, Georgetown, Rehoboth Beach, Chestertown, Centreville, Easton, Denton, Flemington, Somerville, New Brunswick, Freehold, Sandy Hook, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, Mount Holly, Jackson, Millville, Hammonton, Cape May Court House, Ocean City, Atlantic City, Long Beach Island, Wharton State Forest, Media, Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, Chalfont, Perkasie, Morrisville, and Doylestown 258 PM EST Thu Dec 22 2022 ...WIND CHILL ADVISORY IN EFFECT FROM 6 PM FRIDAY TO 10 AM EST SATURDAY... * WHAT...Very cold wind chills expected. Wind chills as low as 10 below zero. * WHERE...Portions of central, northern and southern Delaware, northeast Maryland, central, northern, northwest and southern New Jersey and southeast Pennsylvania. * WHEN...From 6 PM Friday to 10 AM EST Saturday. * IMPACTS...The cold wind chills could result in hypothermia if precautions are not taken. * ADDITIONAL DETAILS...A strong cold front will move through Friday bringing a very sharp drop in temperatures with strong southerly winds shifting to strong westerly. By Friday evening, this combination of wind and cold will result in wind chills dropping below zero with wind chills as low as 10 below expected overnight Friday night into early Saturday. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use caution while traveling outside. Wear appropriate clothing, a hat, and gloves. && $$ Fitzsimmons Wind Advisory URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 256 PM EST Thu Dec 22 2022 DEZ001>003-MDZ012-015-019-020-NJZ001-007>010-012-015>019-021- PAZ054-055-060>062-070-071-101>106-231000- /O.EXB.KPHI.WI.Y.0014.221223T1100Z-221224T0000Z/ New Castle-Kent-Inland Sussex-Kent MD-Queen Annes-Talbot-Caroline- Sussex-Warren-Morris-Hunterdon-Somerset-Middlesex-Mercer-Salem- Gloucester-Camden-Northwestern Burlington-Cumberland-Carbon- Monroe-Berks-Lehigh-Northampton-Delaware-Philadelphia- Western Chester-Eastern Chester-Western Montgomery- Eastern Montgomery-Upper Bucks-Lower Bucks- Including the cities of Wilmington, Dover, Georgetown, Chestertown, Centreville, Easton, Denton, Newton, Washington, Morristown, Flemington, Somerville, New Brunswick, Trenton, Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, Mount Holly, Millville, Jim Thorpe, Stroudsburg, Reading, Allentown, Bethlehem, Media, Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, Chalfont, Perkasie, Morrisville, and Doylestown 256 PM EST Thu Dec 22 2022 ...WIND ADVISORY IN EFFECT FROM 6 AM TO 7 PM EST FRIDAY... * WHAT...Southwest winds 20 to 30 mph with gusts up to 50 mph expected. * WHERE...Portions of central, northern and southern Delaware, northeast Maryland, central, northern, northwest and southern New Jersey and east central, northeast and southeast Pennsylvania. * WHEN...From 6 AM to 7 PM EST Friday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. * ADDITIONAL DETAILS...A brief period of wind gusts near 60 mph is possible as a strong cold front races through the area from late morning to early afternoon Friday. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. && $$ Philly's public schools will be all-virtual tomorrow due to the forecast. Currently light rain and 45 here with dp 45 and 0.42" of rain.

That probably would work in an ENSO neutral/El Nino scenario in another month or so. The front is moving too fast to have had us have enough of a sustained antecedent cold though. And even with that, this scenario has that MW cutter low bombing out and taking all the thunder out of all the other little lows. Temp still rising and I'm now up to 42 with dp 42 and 0.38" in the bucket.

Temp still rising here IMBY and at 39 with dp 39. Have 0.21" in the bucket so far and currently have light rain. Am getting rain up against my back windows that face NE and checked to see the low getting ready to emerge off the coast. So between that and the highs up over Maine and NE Canada, am getting that easterly component.

Rain is steadier and temp continues to rise and is at 37 with dp 36. Have 0.09" so far and the winds have also picked up. We are also in a New Moon phase so this would exacerbate any coastal flooding (although not as much as would have occurred from a Full Moon).

Finally tipped the bucket for 0.01". Since there is a flood watch up for the area, much more to come today and tomorrow. Still 36/dp 34.

Saving that for when the cold front comes blasting through! Temp still 36 and dp now up to 34. Finally moistened up enough for some visible light rain. Bucket hasn't tipped yet though.

Am getting some intermittent light drizzle but every time I stick my head out the door, I don't see/feel anything but it has wet much of the walk. Still not enough to be measurable. Temp still 36 with dp 33.

Decided to go ahead and make an OBS thread for this since we have some NW/Poconos area and LV posters who may see some measurable that will hang around for awhile.

Since we do have a variety of forum posters in areas that will see snow/sleet/ZR - at least initially and on the backend, plus there is a flood threat, along with some potential advisory-level winds and possibly record breaking cold, decided to go ahead and make an obs thread. Currently misty and mostly virga and 36 with dp 32 here in NW Philly.

My Upper Darby sis texted about 5 minutes ago about getting some sleet so some of the yellows on the radar may be ip. I have droplets on the walk, so must have had a drive-by bunch of splats of something (it wasn't actively doing anything when I popped out to investigate). Temp is 36 with dp 32. ETA - my Wyndmoor sis texted to say she had some sleet so since I'm a couple miles SE of her, my spats may have been ip-related although I seem to doubt it as she is at the bottom of a rolling hill (I am actually "above" her in elevation) and she always runs colder than me as the cold air will drain down and settle along her location.

From Mt. Holly - Temp still creeping up here and I'm currently at 35 with dp also up to 31. I had just popped out about 20 minutes ago and have virga over me but you could almost feel and breath the chilled mist in the air!

Stuff on the radar to the west. Currently 33 (temp has been creeping up from a 29 low at midnight), with dp 27.

That may turn out to be a unique record-breaking bomb cyclone. As it is, this is just the first month of met winter and historically the snow was more a January-February (peak winter) thing. In fact recently, we have been getting more in March too as if we were in Colorado. I made it up to 39 today after a low of 25 and it's currently 30 with a dp that has slowly crept up this afternoon from the low 20s to 24.

You forgot this illustration -->

Flood Watch just issued for part of the CWA - Flood Watch Flood Watch National Weather Service Mount Holly NJ 327 PM EST Wed Dec 21 2022 DEZ001-NJZ016>019-PAZ070-071-102-104-106-220830- /O.NEW.KPHI.FA.A.0006.221222T1800Z-221223T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ New Castle-Salem-Gloucester-Camden-Northwestern Burlington-Delaware- Philadelphia-Eastern Chester-Eastern Montgomery-Lower Bucks- Including the cities of Wilmington, Philadelphia, Morrisville, Media, Norristown, Kennett Square, Camden, Glassboro, Mount Holly, Doylestown, Cherry Hill, Moorestown, Pennsville, Lansdale, and West Chester 327 PM EST Wed Dec 21 2022 ...FLOOD WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH FRIDAY MORNING... * WHAT...Flooding caused by excessive rainfall is possible. * WHERE...Portions of northern Delaware...southern New Jersey...and southeast Pennsylvania...including the following areas...in northern Delaware...New Castle. In southern New Jersey...Camden, Gloucester, Northwestern Burlington, and Salem. In southeast Pennsylvania...Delaware, Eastern Chester, Eastern Montgomery, Lower Bucks, and Philadelphia. * WHEN...From Thursday afternoon through Friday morning. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. Creeks and streams may rise out of their banks. Flooding may occur in poor drainage and urban areas. * ADDITIONAL DETAILS... - http://www.weather.gov/safety/flood $$

The Korean War (UN police action) Armistice Treaty was finally signed in 1953, so they still had that need! I grew up hearing about the "rolling hills of Chester County" yet you had "rolling steel" there too, with plants that had popped up along the rivers and creeks for over a century and a half. Another interesting article on that steel plant in Coatesville. And IIRC, W.T. Gordon's son worked at that plant back in the late 1800s/early 1900s.

Let me posit something - and it is related to the deep dive you recall I did of the Coatesville observer W.T. Gordon. Oddly enough I just never knew there were steel plants just outside of Philly in Coatesville because so much focus was always put on U.S. Steel in Pittsburgh and Bethlehem Steel up in the ABE area. I should have probably known better given we had the big Budd plant here in the city cranking out steel parts for cars, planes, and for what was more talked about when I was growing up - trains. When you look at your gathered temp rises and falls, you'll see that interestingly enough, they correspond with a build up leading to a peak right during the main part of WW2. The Coatesville plant was apparently making rolled steel plates where there was mention in an article I just read, would eventually be used in shipbuilding. Of course we had the Navy Yard here down in South Philly with a massive amount of shipbuilding going on all during that period. I.e., all the "Rosie the Riveters". I even had one of my aunts and her friends who briefly worked down at the Navy Yard during that period in the '40s. Once the war was over, boom! All that heavy manufacturing dropped off precipitously and eventually switched to a different type manufacturing output - homes and suburban "office parks"! And as the suburban developments expanded, someone "paved paradise and put up a parking lot" creating some mini-heat islands where they didn't exist before. This was all the post-WWII migration from the cities to the rim counties and eventually into what was dubbed "ex-burbia" (the more rural farm areas). With the recognition of that impact, you have more environmental awareness now and all those undeveloped and former rural farming areas stripped for development, have been slowly replanted, and that has helped to mitigate what was overall warming trend in that area's microclimate. In any case, as my obs - after a 29 low yesterday, I made it up to a breezy 39 as a high. It's currently 28 and clear with dp 20.

There's a good write-up for next week here - https://www.severe-weather.eu/global-weather/coldest-arctic-airmass-winter-season-major-storm-christmas-snow-forecast-united-states-canada-mk/ It did confirm to me that the lakes are still mostly ice-free so there is still potential for big lake effect snow events (some that could send streamers into the northern CWA if the winds blow the right way). This is definitely La Nina-ish weather.

6z GFS 2nd verse, same as the 1st...

0z GFS did move the system east making it more the apps runner but like the other globals, is showing some kind of overrunning rain ahead of the arctic front.

It may run into drier air and evaporate. Temp here is 39 with dp 26....

18z GFS has a buncha take-your-pick storms rolling along the bottom of that arctic high... You know it's bad when the clown map has less than the 10:1.

Ukie has some of the storm in range but seems to be on the arctic blast train...