E PA/NJ/DE Spring 2020 OBS Thread

[RedSky]

12z ECM - Frost potential June 1st?

 

 

[Birds~69]

28 minutes ago, RedSky said:

12z ECM - Frost potential June 1st?

 

Yes!

Although it will be more humid this week the highs are down from predictions a couple days ago....

[ChescoWx]

3 hours ago, RedSky said:

12z ECM - Frost potential June 1st?

 

 

fake news!

[ChescoWx]

Interesting evening here on the Jersey shore in Sea Isle City NJ....the colder than normal off shore 53 degree water temps making for a painful spring at the beaches. While 5 miles inland today were in the 70's here on the barrier islands no better than the upper 50's for most of our day....we finally cleared out for an hour this evening but as you can see on the attached video the marine layer cloud bank and fog were just off shore and came rolling back in over a 45 minute period this evening....me thinks it will be a tough week to realize any warmer temps here on the Jersey beaches no matter what we see just inland....

[Rtd208]

NWS Mt.Holly ref: Wednesday thru Saturday.

 

.LONG TERM /WEDNESDAY THROUGH MONDAY/... 
  Fairly complicated medium-range forecast today, as a western 
  Atlantic ridge will steer a weak system currently off the 
  Florida coast northward into the Mid-Atlantic by Thursday. This 
  complicates the precipitation forecast Wednesday night through 
  Friday, with the subsequent approach of a strong cold front 
  bringing additional chances for convection through Saturday. The 
  temperature forecast will also be problematic as a result of 
  these systems. 
   
  The 00z model suite poses an interesting set of solutions to our 
  sensible weather Wednesday through Saturday. Perhaps the most 
  problematic portion of the forecast is Wednesday and Thursday, 
  as the operational models consistently depict a weak system off 
  the Florida coast migrating slowly northward on the upstream 
  side of a strong western Atlantic ridge into the Mid-Atlantic by 
  Thursday. Convection looks to accompany the weak surface 
  reflection, as stronger instability noses northward as deep- 
  layer southerly flow promotes warm/moist advection along the 
  East Coast. Timing discrepancies exist amongst the model suite, 
  with the GFS a bit faster than the ECMWF. There are also slight 
  differences in the track of the system, and given the rather 
  compact nature of the system`s associated lift, this track will 
  be rather important to pinpoint for resultant QPF. Current 
  thinking is that areas farther inland may have a better shot of 
  precipitation, so the highest PoPs exist in these areas. Areal- 
  average QPF, speaking of, is not particularly impressive when 
  analyzing model solutions generally, but given the source  
  region of the system and the high-octane air that will advect  
  into the region (PWs approaching 2 inches by Thursday  
  afternoon), locally heavy rainfall seems likely with the  
  stronger convective cores. 
   
  Preceding the weak Thursday system, surface flow will continue 
  to slowly veer to a more south-southeast direction. With 
  increasing boundary-layer dew points and a continued onshore 
  component, would expect another round of fog and/or low clouds 
  Wednesday night. 
   
  As might be guessed, the temperature forecast is a little 
  tricky, especially Thursday with the question marks regarding 
  precipitation coverage. Although I expect it to be seasonably 
  warm, the general trend was to nudge highs downward a bit. If 
  precipitation is lacking and/or periods of reduced cloud cover 
  occur, highs will be warmer than forecast. However, confidence 
  is not high enough to stray much warmer than consensus at this 
  point. 
   
  Precipitation chances remain the primary concern Thursday night 
  and Friday. The weak system on Thursday appears to lift north of 
  the region by Thursday night, but the proximity of an 
  approaching trough will allow several midlevel perturbations to 
  eject northeastward in advance of the primary vort max. 
  Scattered convection seems probable in much of the eastern U.S. 
  Thursday night and Friday. Instability will likely gradually 
  increase through the period as well, especially via diurnal 
  diabatic heating on Friday. As such, the threat of thunderstorms 
  looks to increase through this period, likely culminating Friday 
  night with the approach of a strong cold front. The timing of 
  the front is still under debate, with the GFS noticeably slower 
  than the ECMWF/CMC. Tend to think a slower solution is more 
  probable, owing to the strength of downstream ridging. As such, 
  tended to keep PoPs a little bit higher than consensus on 
  Saturday, which has ensemble support. If the slower solutions 
  verify, Saturday would be another active convective day for 
  portions of the region (especially the southeastern CWA). 
   
  Severe storms are certainly possible on Friday and Saturday, 
  though ambient shear appears rather weak. Thus, coverage of  
  severe storms may be fairly sporadic/transient. Locally heavy 
  rainfall seems probable, particularly in areas of training 
  (slow-moving features in play), as PWs will remain rather high 
  (1.6-2.0 inches, generally). 
   
  As with Thursday, temperatures Friday and Saturday are a big 
  question mark, with cloud cover, precipitation coverage, and 
  frontal timing all playing roles in lowering confidence. Again, 
  with the expectation that precipitation coverage will be 
  sufficiently large, think that straying too far from guidance is 
  unwise at this point. 
   
  After the cold front passes through the region Saturday, 
  temperatures will fall below seasonal averages Sunday into the 
  following work week as a strong surface high builds into the 
  region. Another lengthy period of dry weather looks to occur as 
  well. 
   
  && 

[RedSky]

Tomorrow areas of drizzle, possibly heavy at times. What in the world 

[KamuSnow]

3 hours ago, RedSky said:

Tomorrow areas of drizzle, possibly heavy at times. What in the world 

Maybe they don't know about fog?

[Rtd208]

So much for the threat of heavy rain for Thursday/Friday at least on current model guidance. Have to see if that changes over the next 24 hours.

[Birds~69]

82F/DP 64F

Not horrible but certainly not crisp.

Wonder if weather will be a factor launching SpaceX? 

[Birds~69]

1 hour ago, Birds~69 said:

82F/DP 64F

Not horrible but certainly not crisp.

Wonder if weather will be a factor launching SpaceX? 

Yep, postponed.

[ChasingFlakes]

Will be interesting to see if that line holds together as well as it is for the next 30 miles of eastward movement.  If it makes it out my way it looks like it will be around 6-6:15.  Really muggy but there is a nice breeze.