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jmister last won the day on July 27 2018

jmister had the most liked content!

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About jmister

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    Cherry Hill, NJ

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  1. Something to keep in mind as we figure out who is at risk for icing is that even for this little event today, the short range modeling was a few degrees too warm. Even a 6 hour forecast. As all of us have learned, models underestimate low level cold. At 12z today, PHL was 30. My wx station in Cherry Hill has 29.7 GFS: NAM:
  2. By hour 18 you can see the GFS is trending slightly slower (west) with all features at 500mb
  3. Not just front-end thump, but how about that coastal at the end! Not to mention the temps crash after 12z Sunday, so much of that "rain" is sleet/zr. Saved for posterity. May be the best run of the last several days even if it's from the ICON.
  4. Not hating the look of the NAM at 500mb. The northern portion of the trough is a little further west and just a bit more cut off from the northern branch. May not reflect much difference at the surface, but something to look at.
  5. Great, and bold, discussion by Gorse this morning: For Saturday and Sunday...A significant winter storm is increasing for the northern Mid-Atlantic and Northeast. A split flow regime results in significant energy ejecting into the central and southern Plains while northern stream energy amplifies some across eastern Canada and the Great Lakes. The timing of the northern and southern systems will be key regarding the end results here in the East, as some guidance phases them and therefore the surface low tracks over or just west of our area. The track of the surface low will depend on where the baroclinic zone is placed and tightens, as arctic air will be pouring in on the backside of this storm. All of this will play havoc with not only the precipitation types but also amounts and therefore impacts. Thermal profiles at this point utilizing a multi-model blend has a mess of wintry precipitation for much of the region, however farther south and east a change to rain occurs for a time. The guidance continues to show a wealth of moisture accompanying this storm, therefore where it snows the amounts could be significant and there also could be a zone of icing. The potential for heavy rain, snow and mixed precipitation exists with this system. The signal for this storm remains high among the guidance, therefore the PoPs are in the likely to categorical range. As the surface low traverses our area Sunday, arctic air will begin to overspread our area from the west. Some guidance, most notably the GFS, hinting at precipitation lagging behind the arctic push as several ripples of low pressure track along the cold front and therefore throws moisture (snow) inland for a time. Not sold on this idea just jet, but something to monitor. Guidance suggesting a flash freeze potential Sunday afternoon and night as the arctic air pours in right behind the storm. A mention of this storm continues in the Hazardous Weather Outlook. Based on model trends, you'd think this discussion is for CTP.
  6. I'm seeing 0.57" liquid equivalent snowfall on the 18z GEFS at PHL http://cms.met.psu.edu/sref/ensembles/Plumes.html You can play around and change sites, but it looks like the DC area is not much different than this. I guess P-type schemes may cause some discrepancies.
  7. Just me, or is the temperature legend on the right totally mislabeled? edit: just me. Either way, impressive gradient.
  8. Certainly a fun solution to look at! Surface temps hover around 24 for the duration of the precip. At that temperature, I imagine even heavy rain would freeze on contact with most surfaces. I've never experienced an extreme icing situation like what is portrayed here, but honestly it's one of my winter weather fetishes haha.
  9. jmister

    1/12-1/13 OBS, congrats south. Will Tom be banned?

    32/8 on my weather station. Lots of work to do here before any meaningful snow. For what its worth (probably little), the HRRR seems to be a little behind in the north/east boundary of the light returns right now: (shameless plug for my tool showing differences in observed and simulated radar) https://jmmweather.com/hrrr/
  10. jmister

    12/5 Norlun Trof Obs

    Nice fluffy flakes here! Definitely a bit of a surprise it got this far N/W.
  11. jmister

    Meteorological Fall Banter Thread

    Oops... Nice to have a bust go that way!
  12. HRRR seems to be underdoing the front-end stuff but overdoing the backend:
  13. Well...in about 5 minutes we transitioned fully to sleet and it's coming down HARD. Looks like 3.4" on the table.
  14. 2.7" and still all snow. 30.2 degrees. Hoping this is the start of an overperforming winter!
  15. Add another 1/4" for stupid ruler design... November in the background for reference.