TheClimateChanger

Very nice couplet on radar.

Interesting fire behavior from the Park Fire in California, with a fire tornado spawned by pyroCb.

Based on current trends, it appears likely that DCA will see some months reach mean temperature levels never observed outside of Death Valley prior to the 21st century by the end of this century.

Perhaps more impressive, the current monthly mean temperature of 84.5F would tie for 16th warmest July in the ENTIRE period of record at Miami. Higher July mean temperatures were never observed prior to 1981, and only 4 times prior to 2005 [1981, 1983, 1992 (Pinatubo be damned) and 1998]. The highest pre-1980 mean was 84.0F, set in 1969.

Yeah, 110F with 15-20% humidity, a 20-mph breeze, and a thick pall of acrid smoke greatly dimming the sun/solar radiation probably would not feel that bad tbh.

Saw this on my X feed. Had to share here.

At Miami, the mean of 81.9F would tie for 19th warmest of the 89 years of record in the interval from 1896 to 1986 [inclusive]. So, yeah, even Miami is not a good comparison. Temperatures for the summer to date in DC in 2024 would be well above the median 20th century value for Miami for the period ending July 24. Prior to the very end of the 20th century, heat similar to that experienced in DC would only be expected in Miami a little more than twice a decade.

While still well above the median 18th & 19th century summer to date values for Orlando, Florida... a much more pedestrian ranking. This summer would tie for 37th warmest on record between 1892 & 1997.

Similarly, in the 106-year period beginning in 1892 and ending in 1997 [inclusive], this value was exceeded in only 9 summers at Tallahassee, Florida.

The mean temperature at DCA has been 81.9F for the summer to date. In the 93-year period beginning in 1884 and ending in 1976 [inclusive], this value was exceeded on only 5 occasions in Savannah, Georgia. Those being the summers of 1934, 1939, 1942, 1943 and 1952.

70% chance of 90+ by Sunday for valleys and urban areas. The usual hot spots out your way will probably approach 95F.

The latest PBZ AFD highlighting some of the weather items I discussed yesterday. .LONG TERM /SUNDAY THROUGH WEDNESDAY/... KEY MESSAGES: - Warmer and more humid on Sunday. - A few rounds of disturbances pass to close out the weekend into the middle of next week. - Moderate risk of excessive heat beginning in August. ------------------------------------------------------------------- Further modification of the airmass continues on Sunday which will likely be the warmest day of the forecast period as probabilities sit up to 70% for >90F in the urban areas and valleys, though upper cloud coverage will increase from the southwest and could keep highs a little cooler. Ensemble clusters all absorb a cutoff upper low across the deep South back into the southwest flow aloft and show good agreement on its track through the Ohio Valley, but differ some on the amplification. This will return a more unsettled pattern to close out the end of the weekend into the beginning of next week as a few more disturbances pass through. Thereafter, ensembles still show notably good agreement by mid week in central CONUS ridging which would place our area in northwest flow aloft. While these patterns tend to be dry on average, they are also supportive of rounds of severe weather chances as we experienced in a similar pattern last week. Machine learning does paint a broad-brushed potential for a severe threat by mid week, but details won`t become clear for several more days. In addition, heat concerns return. Accordingly, CPC has issued another moderate risk of excessive heat from August 1st through August 7th. Lastly, with flow aloft extending downstream of the Canadian Rockies, wildfire smoke could make its debut to the Pittsburgh region this year.

.LONG TERM /SUNDAY THROUGH WEDNESDAY/... KEY MESSAGES: - Warmer and more humid on Sunday. - A few rounds of disturbances pass to close out the weekend into the middle of next week. - Moderate risk of excessive heat beginning in August. ------------------------------------------------------------------- Further modification of the airmass continues on Sunday which will likely be the warmest day of the forecast period as probabilities sit up to 70% for >90F in the urban areas and valleys, though upper cloud coverage will increase from the southwest and could keep highs a little cooler. Ensemble clusters all absorb a cutoff upper low across the deep South back into the southwest flow aloft and show good agreement on its track through the Ohio Valley, but differ some on the amplification. This will return a more unsettled pattern to close out the end of the weekend into the beginning of next week as a few more disturbances pass through. Thereafter, ensembles still show notably good agreement by mid week in central CONUS ridging which would place our area in northwest flow aloft. While these patterns tend to be dry on average, they are also supportive of rounds of severe weather chances as we experienced in a similar pattern last week. Machine learning does paint a broad-brushed potential for a severe threat by mid week, but details won`t become clear for several more days. In addition, heat concerns return. Accordingly, CPC has issued another moderate risk of excessive heat from August 1st through August 7th. Lastly, with flow aloft extending downstream of the Canadian Rockies, wildfire smoke could make its debut to the Pittsburgh region this year.

I am on team Artusa. Summer is not over yet!

The moderate risk of extreme heat has been extended for an additional day through August 7, 2024. US Hazards OutlookNWS Climate Prediction Center College Park MD300 PM EDT July 24 2024Synopsis: Coast-to-coast mid-level high pressure is predicted across the contiguous U.S. (CONUS) during week-2. This is associated with favored warmer-than-normal temperatures for most of the Lower 48 states. Excessive heat is most likely across the west-central, central, and northeastern CONUS during the week-2 outlook period. In Alaska, mid-level low pressure is forecasted across most of the state, with the exception of the Aleutian archipelago where mid-level high pressure is favored.Hazards High risk of excessive heat for the south-central Plains and northern and western Missouri, Thu-Mon, Aug 1-5. Moderate risk of excessive heat for the Northeast and Mid-Atlantic region, Thu-Wed, Aug 1-7. Moderate risk of excessive heat for portions of the Interior West, all but far southern portions of the Great Plains, and central portions of the Mississippi Valley, Thu-Wed, Aug 1-7. Slight risk of excessive heat for the Interior West, most of the Great Plains, most of the Mississippi and Ohio Valleys, the Great Lakes region, Northeast, and Mid-Atlantic, Thu-Wed, Aug 1-7. Slight risk of excessive heat for the Central Valley of California, Fri-Wed, Aug 2-7. Rapid Onset Drought risk for portions of the Northern and Central Plains. Detailed SummaryFor Saturday July 27 - Wednesday July 31: WPC Days 3-7 U.S. HazardsFor Thursday August 01 - Wednesday August 07: For the week-2 period, ensemble means favor anomalous mid-level ridging and accompanying positive height departures across the CONUS, with maximum 500-hPa heights of at least 594 dm across the southwestern and south-central states.The week-2 temperature outlook favors above-normal temperatures over almost all of the CONUS. A slight risk of excessive heat is depicted across most of the Lower 48 states outside of the Southeast and southern Texas, and valid for the entire Outlook period. Within this extensive slight risk area, there are two areas where a moderate risk of excessive heat is favored. One area includes the Northeast and much of the Mid-Atlantic region, valid Aug 1-7. The second, larger area includes much of the Interior West, most of the Great Plains, and central sections of the Mississippi Valley, Aug 1-7. Within this second, larger area, there is a high risk of excessive heat for the south-central Plains and adjacent parts of the Mississippi Valley, valid Aug 1-5. A general consensus of temperature and excessive heat guidance indicates actual air temperatures across portions of the Northeast and Mid-Atlantic region may reach well into the 90’s, with heat index values exceeding 100 deg F. For the Plains, maximum air temperatures of 100-105 deg F are expected, with heat index values surpassing 110 deg F over portions of the south-central Plains. A skill weighted, bias-corrected hybrid tool (which considers actual air temperature and heat index), raw temperatures from the ensemble means, and Probabilistic Extremes Tool (PET) temperatures were used in the construction of today’s excessive heat map. Based on these same objective tools, a slight risk of excessive heat is depicted for the Central Valley of California, Aug 2-7, where heat index values may approach or exceed 110 deg F.The subtropical ridge is predicted to be centered over the Four Corners region during week-2, in its climatological position during the summer monsoon season. The 06z and 12z GEFS runs are predicting a tropical cyclone over the eastern Pacific to pass south of the Gulf of California early in the Outlook period. This scenario may trigger a gulf surge of moisture into the American Southwest, with the PET precipitation tool depicting amounts of about 0.5-inch. However, no precipitation hazard is predicted at this time.The heaviest precipitation amounts predicted during this outlook period range from 1.0-1.5 inches over a 3-day period, focused along the Southeast and Gulf Coasts. However, normal weekly precipitation amounts for those areas range from 1.0-1.5 inches in most areas to almost 2 inches along the Gulf coast of Florida. Therefore, no precipitation hazards are depicted on today’s hazards map. However, according to the experimental Flood Hazard Outlook, this amount of precipitation is enough to renew flooding chances across the eastern coastal region of North Carolina, which recently experienced heavy precipitation and has elevated soil moisture anomalies.The combination of continued above-normal temperatures and below-normal precipitation supports the continuation of a Rapid Onset Drought (ROD) risk over many parts of the Northern and Central High Plains. Dry soils, stressed vegetation, and reduced water availability due to low ponds and streams may lead to increased impacts to agriculture and livestock, with some locations already experiencing impacts.No hazards are posted for Alaska during week-2. However, there is a significant chance of accumulating snow for portions of the central and eastern Brooks Range, which could have an impact on people within that area. This possibility will be reassessed tomorrow after looking at the most recent model solutions. Near Juneau, localized flooding may be a concern associated with the glacial outburst flood for the Mendenhall River.Forecaster: Anthony Artusa

CPC refusing to back down on the high heat. Significant flash drought risk over the Plains.

It gets especially intriguing at Hour 51, as it looks like all the smoke gets wrapped up in a giant cyclone. I am not too impressed with modeled concentrations right now. Would want to see more 150 mg/m2 or higher for more significant impacts, IMO.

The view from the RAP-SMOKE is probably better since it shows Canada too. Lots of smoke gathering over central Canada. You can kind of imagine this could make a beeline for Pennsylvania if it were to get caught up in some NW to SE oriented jet stream winds. I think we would need the trough to flatten and push east to get into more of a NW flow pattern.

One thing I haven't seen much discussion of is how the extensive wildfire smoke might affect the upcoming temperatures? We've been fortunate so far that impacts have been minimal, but I do wonder if we won't start to see more smokiness and haze as we head into late summer. There's some evidence that wildfire smoke could lead to lower temperatures. Last summer saw several episodes of dense smoke, and it was the coldest summer at Harrisburg since 2017. Another good analog is 1950. Read about the Chinchaga fire storms, and Black Sunday here in the Commonwealth. Fascinating stuff. 1950 is tied with 1979 for 13th coldest summer at Harrisburg, and it came on the heels of the scorching summer of 1949. After this summer is complete, 1949 will drop into a 3-way tie for 18th warmest [with 2018 & 1955]. However, at the time, the heat of 1949 was nearly unparalleled among records dating to the 19th century, being exceeded only in the summers of 1900 and 1943. Nobody then foresaw a future where a mean of 75.4F would become rather pedestrian at Harrisburg [having been met or exceeded in 11 of the last 23 summers*]. So the drop-off between 1949 & 1950 must have been quite a shocker to the locals - perhaps a bit of a relief as well in those pre-A/C days. *Yes, 2024 is not complete. But the mean will most certainly exceed 75.4F.

But my post was talking about the mean maximum temperature for summer to date, so it sounds like the only thing you really care about is arguing for the hell of it.

After further review, 1949 is missing the entire month of June at MPO. So toss that year, and make it 6th warmest (of 114 years).

You're comparing the mean of 53 days with 1 day? But to answer your question, I have a scorching 88F on the trusty weather station.

Also, I've been told in the past that only maximum temperatures count. That is, that people judge summer heat by maximum temperature, and minimum temperatures don't count. The rankings are very similar across the board for mean maximum temperature. Every site is within 2 places of its mean temperature ranking if re-ranked by maximum temperature, with the exception of MPO and IPT. So we are legit cooking, and it's not just some overly inflated minimum temperatures.

I think there's a reason to expect extreme heat at some point in the 6-14 day timeframe when CPC is saying there's an 80-90% chance heat index readings reach at or above the mid to upper 90s.