Pittsburgh/Western PA Summer 2023

[Ahoff]

Could be one of the coldest June highs in a few years.

Edit: Nevermind.  Temps seemed sluggish earlier, lol.

[TimB]

On 6/21/2023 at 12:02 PM, Ahoff said:

Yesterday's low of 66 has been the warmest of the year so far.  Sunday night is forecast for a 66 degree low.  If that stays as the warmest low for the month it will be since 2006 the highest low in June was that cool.  Possible we do it too.

Also, May's warmest low was 60 that's the coolest maximum low in May since 2005.

This looks safe, though I suspect we start getting some upper 60s lows as soon as July starts.

[TheClimateChanger]

Lots of filthy air upstream slowly advecting into western Pennsylvania in the northwest flow.

[Ahoff]

5 hours ago, TimB said:

This looks safe, though I suspect we start getting some upper 60s lows as soon as July starts.

Yeah, has not been warm this month.

[KPITSnow]

Very Smokey today. Honestly found it kind of amazing that I checked theAFD yesterdat and there was no mention of it. Only added it later in the night.

 

given how this was obviously coming surprised it wasn’t discussed 

[TimB]

18 minutes ago, KPITSnow said:

Very Smokey today. Honestly found it kind of amazing that I checked theAFD yesterdat and there was no mention of it. Only added it later in the night.

 

given how this was obviously coming surprised it wasn’t discussed 

PBZ’s AFD left out a major detail? You don’t say.

[KPITSnow]

8 minutes ago, TimB said:

PBZ’s AFD left out a major detail? You don’t say.

Oh they added it but not till yesterday afternoon. 
 

it’s like when a major winter storm is modeled three days out and they basically say there is uncertainty and it’s there without discussion. Meanwhile the neighboring offices will have a novel written. 
 

though I’ll give a bit of a break this time, Ctp also had no mention, bit in general their write ups are always much more detailed 

[TimB]

Just now, KPITSnow said:

Oh they added it but not till yesterday afternoon. 
 

it’s like when a major winter storm is modeled three days out and they basically say there is uncertainty and it’s there without discussion. Meanwhile the neighboring offices will have a novel written. 
 

though I’ll give a bit of a break this time, Ctp also had no mention, bit in general their write ups are always much more detailed 

But they post those little graphics on their social media pages saying we can expect between 0 and 14 inches of snow, so even if the discussion is lacking we still know what to expect.

[Ahoff]

Yeah, I'm over this smoke, lol.  Isn't any rain getting to these wildfires, since it seems Canada has no interest in stopping them?

[meatwad]

Smells like burnt plastic outside.

[Ahoff]

78 will be pretty tough today.  Wonder why forecasts insist on staying there if smoke will stay this thick?

[KPITSnow]

We’ve certainly had some unique weather recently. Long dry spell. A long period with dew points 50 and under In may and June and the least humid upper 80’s days I can remember and lows in the lower 50’s. Now the smoke. 

[TimB]

Going to badly bust low on today’s high temperature, even without the smoke. Not that I’m complaining. Should allow us to squeak out a top 20 coldest June.

[jwilson]

The long-term pattern still not showing much sign of abating.  The west dries up, and while we aren't quite as dramatically under a trough the whole time, we're still wet-looking for almost the entire period.  Really everywhere from the plains on east.

2-3" over the next week.

[Ahoff]

Yeah, really laughable how poorly this smoke and weather pattern was forecast.

Wish we could get that drought weather back, but alas we’ll probably have a top ten wet July, just because, lol.

[TimB]

4 minutes ago, Ahoff said:

Yeah, really laughable how poorly this smoke and weather pattern was forecast.

Wish we could get that drought weather back, but alas we’ll probably have a top ten wet July, just because, lol.

For reference, the magic number for 10th place is 7.32” in 2012.

[TimB]

With today’s high of 79 being more or less official, that seals the deal that June will finish with 10 days reaching 80 or above, the 15th time in the period of record there have been that few or fewer. We did this as recently as 2019 and also in 2003.
 

But 4 of those days came at the start of the month. This will be the 6th year in the period of record and first since 1982 that there have been 6 or fewer 80 degree days from 6/5 to 6/30.

[Ahoff]

4 hours ago, TimB said:

For reference, the magic number for 10th place is 7.32” in 2012.

Honestly, looks possible, lol.

[KPITSnow]

Lots of flash flood warnings but no real severe activity or for that matter even a ton of lightning. Had to abandon after 14 holes at north park today but the rain coming on the 9th was a blessing. It was brutal 

[TheClimateChanger]

Unbelievably heavy rain with these storms.

[KPITSnow]

Could certainly see flooding issues today if there is a repeat of yesterday. In the north hills a bunch of the creeks are pretty high so adding more storms like yesterday will cause some to spill over 

[north pgh]

Tornado Warning

Severe Weather Statement
National Weather Service Pittsburgh PA
647 PM EDT Sun Jul 2 2023

OHC019-067-157-022300-
/O.CON.KPBZ.TO.W.0003.000000T0000Z-230702T2300Z/
Harrison OH-Carroll OH-Tuscarawas OH-
647 PM EDT Sun Jul 2 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM EDT FOR
NORTHWESTERN HARRISON...SOUTHWESTERN CARROLL AND EAST CENTRAL
TUSCARAWAS COUNTIES...

At 647 PM EDT, a severe thunderstorm capable of producing a tornado
was located near Dennison, or near Uhrichsville, moving east at 30
mph.

HAZARD...Tornado.

SOURCE...Weather spotters reported a funnel cloud.

IMPACT...Flying debris will be dangerous to those caught without
         shelter. Mobile homes will be damaged or destroyed. Damage
         to roofs, windows, and vehicles will occur.  Tree damage is
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
northwestern Harrison, southwestern Carroll and east central
Tuscarawas Counties, including the following locations... Leesville,
Sherrodsville, Leesville Lake Park, and Bowerston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Please report severe weather by calling 412-262-1988, posting to
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH.

&&

LAT...LON 4039 8134 4048 8133 4052 8123 4047 8112
      4037 8115
TIME...MOT...LOC 2247Z 271DEG 24KT 4044 8124

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Frazier

---

[KPITSnow]

This storm is going to train right over some areas in the north hills that got blasted yesterday. Imagine we see a flash flood warning very soon 

[meatwad]

Flash Flood Warning

Flash Flood Warning
PAC003-007-125-WVC009-029-030345-
/O.NEW.KPBZ.FF.W.0008.230703T0041Z-230703T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
841 PM EDT Sun Jul 2 2023

The National Weather Service in Pittsburgh has issued a

* Flash Flood Warning for...
  West Central Allegheny County in southwestern Pennsylvania...
  Northwestern Washington County in southwestern Pennsylvania...
  South Central Beaver County in western Pennsylvania...
  Brooke County in northern West Virginia...
  Hancock County in northern West Virginia...

* Until 1145 PM EDT.

* At 841 PM EDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Between 0.5 and 1.5 inches of
  rain have fallen. Additional rainfall amounts of 1 to 2 inches are
  possible in the warned area. Flash flooding is ongoing or expected
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Moon Township, Weirton, Coraopolis, Sewickley, Imperial, Frankfort
  Springs, Hanover Township, Raccoon Creek State Park, Pittsburgh
  International Airport, Enlow and North Fayette Township.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don`t drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4047 8053 4049 8050 4054 8020 4051 8015
      4044 8020 4040 8040 4039 8052

FLASH FLOOD...RADAR INDICATED

$$

Miller

[Ahoff]

CPC's most recently monthly outlook for July (released June 30), has higher chances of above average temperatures for July.  Every other extended outlook (6-10 day, 8-14 day, and 3-4 week out to July 28th) has higher chance of below normal temps.  How can they be that at odds with themselves?

No fear though, they are locked into rainier than normal for the month on every outlook.

[TimB]

22 minutes ago, Ahoff said:

CPC's most recently monthly outlook for July (released June 30), has higher chances of above average temperatures for July.  Every other extended outlook (6-10 day, 8-14 day, and 3-4 week out to July 28th) has higher chance of below normal temps.  How can they be that at odds with themselves?

No fear though, they are locked into rainier than normal for the month on every outlook.

I did notice that. I would assume it has something to do with different personnel doing the different outlooks and/or data from different dates being used.

[Ahoff]

55 minutes ago, TimB said:

I did notice that. I would assume it has something to do with different personnel doing the different outlooks and/or data from different dates being used.

Just really strange.  Four weeks of more likely below average turns out above average for the month, lol.

[TheClimateChanger]

2 hours ago, TimB said:

I did notice that. I would assume it has something to do with different personnel doing the different outlooks and/or data from different dates being used.

Looks like it could just be the use of different data. The monthly outlooks appear to rely on data from certain sources. The week 3-4 outlooks appear to have more human input. Based on this discussion, it looks like a cooler and wetter second half of July, with periods of smoke and haze from Canadian wildfires.

Prognostic Discussion for Week 3-4 Temperature and Experimental Precipitation Outlooks
NWS Climate Prediction Center College Park MD
300PM EDT Fri Jun 30 2023

Week 3-4 Forecast Discussion Valid Sat Jul 15 2023-Fri Jul 28 2023

This Week 3-4 temperature and precipitation outlook is for the period of July 15 - July 28, 2023, which is climatologically near the warmest two-week period of the year for much of the United States. June has been characterized by a tripole pattern of temperatures across the contiguous U.S. (CONUS): 1) record warmth in the southern CONUS, particularly in Texas, 2) below normal temperatures in the middle tier of states from California to the East Coast, and 3) above normal temperatures from the Pacific Northwest to the Great Lakes. This pattern is largely consistent with the weak teleconnection that is associated with El Niño during summer, which consists of zonally-elongated troughing of 500-hPa heights across the middle of CONUS with anomalous ridging both to the north and the south. Currently, Niño 3.4 sea surface temperature (SST) anomalies exceed +0.9 degree C, thus El Niño may continue to act as a weak background forcing. In fact, the Climate Prediction Center's (CPC) current Week 2 outlook is remarkably consistent with a weak El Niño teleconnection persisting.

Other physical drivers considered for this outlook include the Madden Julian Oscillation (MJO), extratropical SSTs, soil moisture, the North Atlantic Oscillation (NAO), the Pacific-North American pattern (PNA), the long-term trend, and the ongoing Canadian wildfires. The Real-time Multivariate MJO (RMM) indices are currently weak, and they are forecasted to remain so over the coming weeks, with no coherent propagating signal. Thus, the MJO is not expected to have a meaningful impact on the Week 3-4 circulation pattern. Extratropical SSTs are below normal along the southern Alaska coast and the West Coast. They are above normal in the Gulf of Mexico and along the East Coast. The greatest soil moisture anomalies currently reside in the Mid-Mississippi River Valley, where much of the region is below the 10th percentile of climatology. However, conditions are likely to improve there as the current Weather Prediction Center's (WPC) quantitative precipitation forecast shows much of the region receiving 2 to 4” of rain over the coming week. The NAO is forecast to remain negative through Week 2, while the PNA is forecasted to be neutral. However, dynamical model guidance for Week 3-4 indicates that the NAO may persist in its negative phase while the PNA may trend toward positive values. These phases of NAO and PNA would increase the chances for troughing over eastern CONUS. With respect to the long-term trend, it is toward warmer temperatures across all of CONUS and Alaska. Finally, the Canadian wildfires have been a permanent fixture this summer. Smoke from these fires has intruded into CONUS regularly under anomalous northwesterly flow. Hazy skies produced by smoke generally reflect insolation, decreasing day time highs slightly. However, at night, smoke is a relatively inefficient longwave absorber/re-emitter and thus has little impact on nighttime lows. Therefore, the overall impact of the smoke is to lower temperatures slightly.

The Week 3-4 temperature and precipitation outlooks take into consideration the El Niño teleconnection, the aforementioned physical drivers, and a blend of dynamical model guidance from the European Centre for Medium-Range Weather Forecasts (ECMWF), Climate Forecast System version 2 (CFSv2), Japan Meteorological Agency (JMA), and, to a lesser extent, the The Global Ensemble Forecast System version 12 (GEFSv12). The GEFSv12 was an outlier with respect to the other models. The forecasted 500-hPa height anomalies indicate ridging centered over the Aleutians and broad positive anomalies over Canada and western CONUS. Some troughing is centered over the Great Lakes in Week 3 that relaxes toward neutral anomalies during Week 4. With respect to western CONUS, the positive height anomalies are largest in the Desert Southwest and are near zero in the Pacific Northwest during Week 3. This overall pattern resembles the tripole, El Niño-like teleconnection described above.

For the temperature outlook, above normal temperatures are forecasted in the southern CONUS. The Desert Southwest has the highest probabilities of above normal temperatures, being located under the ridge. Moreover, some internal, experimental tools are showing elevated probabilities of excessive heat in the region. A broad region of weakly enhanced probabilities of below normal temperatures are indicated from South Dakota southward and eastward to the Ohio Valley and Great Lakes. While most model guidance forecasted near zero anomalies in this region, the eastern CONUS has consistently verified below normal this summer due to persistent northwesterly flow and possibly due to the dampening influence of smoke on daytime highs. The smoke and haze is likely to continue, as the anticipated ridging over Canada promotes conditions favorable to wildfires and also provides northwest flow that advects the smoke into the eastern CONUS. Above normal temperatures are favored in the extreme northern tier of CONUS, where the impact of any ridging in western Canada will be most felt. Finally, most guidance agrees on enhanced probabilities of below normal temperatures in southwestern Alaska under northerly flow and above normal temperatures in northeastern Alaska under westerly flow.

With respect to precipitation, northerly flow due to the presence of upstream ridging over the Aleutians promotes below normal precipitation over southern Alaska and above normal precipitation in northern Alaska. Below normal precipitation is likely over the Desert Southwest, under the influence of ridging. Above normal precipitation is forecasted from the Northern Plains to the East Coast, consistent with anomalous upper-level cyclonic flow in the region.

Finally, for Hawaii, the multi-model ensemble from the Subseasonal Prediction Experiment (SubX) shows the highest probabilities of above normal temperatures in the northwestern islands, consistent with observed SST gradient. Below normal precipitation is favored in the southeastern islands and above normal precipitation is favored in the northwestern islands.

 

[Ahoff]

Wonder if we have a wall to wall cool summer?  Must be a while since that happened.

[Ahoff]

16 hours ago, Ahoff said:

Wonder if we have a wall to wall cool summer?  Must be a while since that happened.

Update to this.  Summer 2009 had a below average June and July and an exactly average August.  But 2004 was the last year that each summer month was below the averages.