E PA/NJ/DE Spring 2025 Obs/Discussion

[Birds~69]

I guess we get screwed out of seeing Haley's Comet debris/showers in the  early morning hours pre dawn tomorrow due to cloudy skies...

[RedSky]

Did the Atlantic dry up in the drought why is there little moisture with a southeast fetch

[RedSky]

Still a precipitation black hole in southern Chester County, amazing stuff

 

[Birds~69]

Radar showing a little pulse...

66F/DP 63F

[RedSky]

Steady rain shower 

[ChescoWx]

0.23" of rain since this morning here in East Nantmeal this brings our 3 day total up to 1.51" of rain.

[LVLion77]

Well, Sunday and Monday were highly inaccurate forecasts with 0.08” yesterday and a 0.00 today. Still convinced the east wind has stabilized the atmosphere to the point that heavy showers and tstorms are unable to form in this quadrant of this system. We go to a more southerly flow on Tuesday, which should be more conducive to heavier rain.

[RedSky]

.20" Monday 

2.40" total

 

[JTA66]

Picked up .90” early this morning.

[ChescoWx]

A 4th consecutive day of showers with .09" since midnight. We have now picked up 1.67" since Saturday. Some more showers and even a PM thunderstorm in spots today. Rain chances diminish tonight but pick back up again by Thursday afternoon and evening. We finally clear out by the weekend. Chillier temperatures on Saturday but a nice warmup by Mother's Day.

[Albedoman]

9 hours ago, LVLion77 said:

Well, Sunday and Monday were highly inaccurate forecasts with 0.08” yesterday and a 0.00 today. Still convinced the east wind has stabilized the atmosphere to the point that heavy showers and tstorms are unable to form in this quadrant of this system. We go to a more southerly flow on Tuesday, which should be more conducive to heavier rain.

absolutely agree. Forecast models have continually failed with wind speed and direction since last year.  The LR and even the SR computer models need to be calibrated to not just look at temps and precip atmospheric profiles and soundings but should consider the most critical feature- the role of surface topography and overall natural physical geography of our area. 

For example when a SE to S direction fetch of wind is prevalent for hours or days, the models should compare the geography of the area and bias should be added for chances of higher precip values(especially in training t-storms or froneneis for snowfall predictions )  in certain regions of the entire forecast area for MT Holly.  The same goes with a direct east wind in which literally prevents t storms from from the west to cross over the Blue Mts. Physical Geography features plays a vital part in local forecasting for our area and atmospheric modeling needs to be vastly improved to include and or be more accurately biased when using pin point forecasting, especially with wind direction speed for upsloping and downsloping of the mountain ranges and deeper valleys.  Simplistic terms- need a better algorithm for physical geography features rather than just using transportation networks to identify different forecasts for different aras. Thats why Macungie to Huffs Church area are constantly having inaccurate forecasting  for either high or low temps and or precip values and types  because the pin-point forecast do not include the topography for S Mtn range as a dividing line for precip or for different forecasts.  Everything is now based on I-78, I-80 and PA turnpike transportation areas when formulating and discussing the local forecasts.

IMHO, MT Holly /NOAA needs to reconsider relying more on physical geography/topography when discussing LV forecasts and not  just referring to major transportation networks. FWIW, transportation networks literally bore through local mountain ranges by tunnels or by steep climbing lanes and built to go in different directions. I -78 is a perfect example of how dividing forecast areas is incorrect as it goes from SW to NE and then goes directly E to West. It literally bisects the S Mt Range in the heart of the LV.  The NE turnpike is a N to S directional road which is usually only brought into the picture on types of winter precip or from storms along the coast--- yet both of these highways go through the heart of the LV.. Hopefully you see the problem of using transportation networks as delimiting line for producing local forecasts in the LV. 

Best examples of my reasoning- how many times have you personally gone through the Lehigh Tunnel and on one side it is snowing and the other side it is clear?  How many times have you gone on RT 29/Rt 100 through  Shimerville or Huffs Church and it has 2 in of snow on the ground  but you get to the Macungie and Emmaus and or East Greenville  and it is raining? Physical Geography plays a vital part in weather  forecasting and personally believe not enough attention has been given to this  fact based on our vast local regional forecasting area that MT Holly must cover.  This is not the fault of the MT Holly staff at all  but federal govt decisions made back in the early 90's to do away with the Allentown weather forecast office at LVIA. This was a huge mistake and I was against  this change but it was a lost cause. The politicians simply did not care or understand the role of physical geography has on the the LV . That is why I am so outspoken at times about the LV. The "fall Line"" basically stops at S MT range and any thing north of that that is also in a valley which has very unique weather forecasting difficulties such as extreme diurnal and nocturnal temp ranges from the deeper valleys especially with upsloping and downsloping conditions in major storm events including wind storms, fog, freezing rain and even snow accumulations. LV is unique. 

[LVblizzard]

Eastern PA just upgraded to a slight risk. Hopefully I can see one good storm because I’m about to leave for my yearly storm chasing vacation tomorrow and the pattern looks abysmal for at least the first half of it.

[The Iceman]

Mesoscale Discussion 0716
NWS Storm Prediction Center Norman OK
May 6, 2025 16:01Z

Areas affected...portions of eastern Pennsylvania into western New Jersey and far southeast New York

Concerning...Severe potential...Watch possible

Valid 061601Z - 061800Z

Probability of Watch Issuance...60 percent

SUMMARY...The severe threat should gradually increase over the next several hours. The stronger storms will be capable of strong wind gusts and perhaps large hail. A Severe Thunderstorm Watch issuance may be needed if appreciable strong storm coverage becomes apparent.

DISCUSSION...Insolation is modifying the boundary layer amid some persistent cloud cover, remnant from earlier showers and thunderstorms, which is warming temperatures through the 60s F. Cooling temperatures atop a destabilizing airmass from the approach of a pronounced upper trough, and minimal convection inhibition, is supporting relative robust updraft development across southeast PA (per MRMS mosaic radar imagery). Through the day, further heating should boost MLCAPE to over 1000 J/kg, which should be adequate for scattered strong to potentially severe storms given expected 40-50 kts of effective bulk shear. Current regional VADs and short-term RAP forecast soundings depict a unidirectional vertical wind profile with elongated, straight hodographs. As such, linear multicellular clusters and transient supercells should be the primary modes of convection for the stronger storms that manage to develop. Strong, damaging gusts are possible later this afternoon once the boundary layer destabilizes. Given colder temperatures aloft overspreading the Mid-Atlantic into the Hudson Valley, large hail cannot be ruled out either. Therefore, if robust storm coverage becomes apparent, a Severe Thunderstorm Watch may be needed within the next few hours.

..Squitieri/Gleason.. 05/06/2025

 

suns out here in Levittown now

[Hurricane Agnes]

Watches are up.

Quote

SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 233
NWS STORM PREDICTION CENTER NORMAN OK
105 PM EDT TUE MAY 6 2025

SEVERE THUNDERSTORM WATCH 233 IS IN EFFECT UNTIL 800 PM EDT
FOR THE FOLLOWING LOCATIONS

PAC011-015-017-025-029-037-043-045-069-071-075-077-079-089-091-
093-095-097-101-103-107-113-115-127-131-133-070000-
/O.NEW.KWNS.SV.A.0233.250506T1705Z-250507T0000Z/

PA
.    PENNSYLVANIA COUNTIES INCLUDED ARE

BERKS                BRADFORD            BUCKS
CARBON               CHESTER             COLUMBIA
DAUPHIN              DELAWARE            LACKAWANNA
LANCASTER            LEBANON             LEHIGH
LUZERNE              MONROE              MONTGOMERY
MONTOUR              NORTHAMPTON         NORTHUMBERLAND
PHILADELPHIA         PIKE                SCHUYLKILL
SULLIVAN             SUSQUEHANNA         WAYNE
WYOMING              YORK
$$


ATTN...WFO...PHI...CTP...BGM...

 

Quote

SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 233
NWS STORM PREDICTION CENTER NORMAN OK
105 PM EDT TUE MAY 6 2025

SEVERE THUNDERSTORM WATCH 233 IS IN EFFECT UNTIL 800 PM EDT
FOR THE FOLLOWING LOCATIONS

NJC019-021-027-035-037-041-070000-
/O.NEW.KWNS.SV.A.0233.250506T1705Z-250507T0000Z/

NJ
.    NEW JERSEY COUNTIES INCLUDED ARE

HUNTERDON            MERCER              MORRIS
SOMERSET             SUSSEX              WARREN
$$

 

Have been getting on and off popcorn type little cells and streamers this morning and have 0.03" in the bucket from a couple.  The sun did come out a couple hours ago so things are destabilizing.  There has been a series of bands basically training, N->S, over portions of Lancaster and York Counties for hours. I know it has to be flooding there.

I bottomed out at 60 this morning and have been bopping around 75/76 as a high so far. Currently 76 and partly sunny (but with some serious-looking angry cumulostratus off to the east) and a dp of 67.

[LVblizzard]

That's a really nice looking cell near West Chester. Even has somewhat of the classic supercell shape on radar. It's headed right towards me, ETA just over an hour...might go and chase it if it perks up again.

[ChescoWx]

Heavy Tstorm in progress here in NW Chester County

[Mikeymac5306]

36 minutes ago, LVblizzard said:

That's a really nice looking cell near West Chester. Even has somewhat of the classic supercell shape on radar. It's headed right towards me, ETA just over an hour...might go and chase it if it perks up again.

Missed us to the west. Looked good from afar though

[Birds~69]

10 hours ago, JTA66 said:

Picked up .90” early this morning.

Same, got smoked by rain early morning... Gusty winds now at 5:00 p.m. 

[MGorse]

0.11 inches of rain the past few days. Yup, that’s it. 

[Albedoman]

nothing but sprinkles here today in Macungie.  Missed everything. Total four day is .46 in---- Storms to the west and east and we got the 4-10 split. Well better luck next time. When are we ever going to have a decent NW to SE squall line come through? Everything is hit and miss in our region I literally cannot remember when a squall line preceded a cold front as so many squall lines have went ---poof ---before hitting the Blue Mts.

[LVLion77]

absolutely agree. Forecast models have continually failed with wind speed and direction since last year.  The LR and even the SR computer models need to be calibrated to not just look at temps and precip atmospheric profiles and soundings but should consider the most critical feature- the role of surface topography and overall natural physical geography of our area. 
For example when a SE to S direction fetch of wind is prevalent for hours or days, the models should compare the geography of the area and bias should be added for chances of higher precip values(especially in training t-storms or froneneis for snowfall predictions )  in certain regions of the entire forecast area for MT Holly.  The same goes with a direct east wind in which literally prevents t storms from from the west to cross over the Blue Mts. Physical Geography features plays a vital part in local forecasting for our area and atmospheric modeling needs to be vastly improved to include and or be more accurately biased when using pin point forecasting, especially with wind direction speed for upsloping and downsloping of the mountain ranges and deeper valleys.  Simplistic terms- need a better algorithm for physical geography features rather than just using transportation networks to identify different forecasts for different aras. Thats why Macungie to Huffs Church area are constantly having inaccurate forecasting  for either high or low temps and or precip values and types  because the pin-point forecast do not include the topography for S Mtn range as a dividing line for precip or for different forecasts.  Everything is now based on I-78, I-80 and PA turnpike transportation areas when formulating and discussing the local forecasts.
IMHO, MT Holly /NOAA needs to reconsider relying more on physical geography/topography when discussing LV forecasts and not  just referring to major transportation networks. FWIW, transportation networks literally bore through local mountain ranges by tunnels or by steep climbing lanes and built to go in different directions. I -78 is a perfect example of how dividing forecast areas is incorrect as it goes from SW to NE and then goes directly E to West. It literally bisects the S Mt Range in the heart of the LV.  The NE turnpike is a N to S directional road which is usually only brought into the picture on types of winter precip or from storms along the coast--- yet both of these highways go through the heart of the LV.. Hopefully you see the problem of using transportation networks as delimiting line for producing local forecasts in the LV. 
Best examples of my reasoning- how many times have you personally gone through the Lehigh Tunnel and on one side it is snowing and the other side it is clear?  How many times have you gone on RT 29/Rt 100 through  Shimerville or Huffs Church and it has 2 in of snow on the ground  but you get to the Macungie and Emmaus and or East Greenville  and it is raining? Physical Geography plays a vital part in weather  forecasting and personally believe not enough attention has been given to this  fact based on our vast local regional forecasting area that MT Holly must cover.  This is not the fault of the MT Holly staff at all  but federal govt decisions made back in the early 90's to do away with the Allentown weather forecast office at LVIA. This was a huge mistake and I was against  this change but it was a lost cause. The politicians simply did not care or understand the role of physical geography has on the the LV . That is why I am so outspoken at times about the LV. The "fall Line"" basically stops at S MT range and any thing north of that that is also in a valley which has very unique weather forecasting difficulties such as extreme diurnal and nocturnal temp ranges from the deeper valleys especially with upsloping and downsloping conditions in major storm events including wind storms, fog, freezing rain and even snow accumulations. LV is unique. 

Well said, and I largely agree with everything you’re saying. The forecast have been increasingly inaccurate over time. Like you said, it is a very broad type of forecast. And we are in this specific area of the valley in a very interesting micro climate. Overall, we get a boatload of rain on a yearly basis. We are either getting flooded out, or we go into dry spells as we have recently. Today, even small components of the forecast were very inaccurate. We kept the stable east wind flow right up until about 3 PM, which continued to work it’s magic to keep us very dry. I just finished work and I’m coming home soon, but I’ve been following the radar as much as I could this afternoon and I’m not sure we got more than a 10th of an inch at home.


.

[ChescoWx]

0.61" today here in East Nantmeal. Some other county totals. Avondale 0.69" / Glenmoore 0.48" / Warwick Twp. 0.47" / Devault 0.45"/ Chester Springs 0.25" / KMQS 0.14" / West Chester 0.14" / Nottingham 0.15" / Kennett Square 0.06" / Longwood Gardens 0.05"