TheClimateChanger

I hate that! A lot of TV meteorologists do that as well... de-emphasize the use of "normal" because they say it incorrectly implies other values are abnormal and instead use "average" or "mean." In fact, the NWS normals are not simple averages or means. In some cases, the two can be quite a bit different. There are adjustments for inhomogeneities [pairwise homogenization] and a lot of statistical work behind the scenes to smooth out the data, for instance. So, while calling them "averages" or "means" might be more intuitive for the casual weather viewer, it's not technically correct in the dictionary definition sense.

The 1921-1950 normal at Detroit City Airport (no DTW) was 27.5F. Prior to that period, the "normals" published were just the means of all data from the city and airport.

Normals are not simple averages. You are conflating the published normals with simple averages of data collected from different sites. The normals are - and always have been - corrected for biases and change in instrumentation, site location or other inhomogeneities. Here are two examples, but I'm sure the others are off as well. The 1931-1960 normal at DTW (as revised in 1967) was ~27.3F for the winter (DJF). Versus the corrected normal, this winter was approximately 0.2F above normal [not 0.4F below normal]. The 1941-1970 normal at DTW was ~26.6F for the winter (DJF). Versus the corrected normal, this winter was approximately 0.9F above normal [not 0.3F above normal].

A couple of tornado warnings now in effect east of Pittsburgh. In addition, a wind gust to 76 mph was recorded at Zanesville earlier, as well as a gust to 70 mph at Akron-Canton Airport.

The first 15 days of March have been very, with a mean of 58.3F - the 7th warmest on record. Last year saw the 2nd warmest period with a mean 3F warmer.

Records met or exceeded at all climate sites today, except DuBois. Low 80s common in the south and west parts of the CWA. PIT: 79F HLG: 81F MGW: 80F ZZV: 80F PHD: 78F

Definitely looking pretty intense in the Texas panhandle.

Keep in mind, using the traditional PDSI formula, you need to offset the increase in PET due to temperatures. If temperatures have risen 4-6F since the mid 20th century, then you would need about 3 or 4 more inches of rainfall each year just to offset the increase in PET [assuming an average annual precipitation in the low 40 inch range]. If you have been getting 50" or so, then it's still been overall pretty wet. But, at least, using the PDSI, if precipitation dropped back to 41-42 inches, that would actually a mild to moderate drought. Here's Grok's explanation: \

Not looking too good. Source: NCEI's Climate at a Glance.

I consider the nClimDiv PDSI values as the only reliable measurement of drought, but they are only published once a month. The calculation has been maintained in the same way for the entire dataset. The published Drought Monitor is not always reliable - there seems to be a human bias to verify forecasts, as opposed to purely basing it off of objective temperature & precipitation data. Other sources for the PDSI typically use the self-calibrated version developed in the recent past, which tends to minimize the effect of warming temperatures [temperature is a primary variable in the PDSI formula, due to its impact on PET]. This dataset is the only one that seems reliable when comparing to the past. Here is the divisional map. Southern New Jersey is second driest on record, nearing -5 on the traditional scale.

Wow. The nationwide average PDSI is -3.79, as of the end of February. 16th lowest on record.

It's a nationwide torch right now. I wouldn't be surprised if it's the warmest first 12 days of March on record nationwide. There's been record warmth all over the place.

“Not a cool summer.” I guess that’s one way to frame it. Looks like the hottest summer on record to me? The current hottest summers are 1936 & 2021, both of which were 1.67F above the 1991-2020 mean. This map shows more than half the country 2-3F above normal. Impressive signal for a model superblend three months out.

Overall, I think most people far overestimate past climate variations - particularly on the warm side. 21st century temperatures are likely the warmest globally since the Eemian [and, recent years, are probably not far from the Eemian thermal maximum]. The past natural variations were driven principally by changes in orbit and precession. These changes are most prominent in the summer and driven by the Northern Hemisphere. Keep in mind when the axial tilt is larger, in the wintertime, it's actually tilting even farther from the sun. Changes in the timing of aphelion and perihelion can magnify these effects. So, some of these prior warm periods may have had surprisingly robust winters once the snow and ice coverage started forming. This is why you have even bleeding-heart libs on here who believe it reasonable that DC or the Mid-Atlantic region may have had centuries of little or no snow during the so-called Medieval Warm Period. In fact, there is nothing to support that belief. The propaganda and falsified narratives promoted by the U.S. government and the media are that strong. All reliable global reconstructions confirm we are much warmer today, and the MWP is barely a blip on what otherwise is largely a downward trend from the Holocene Thermal Maximum about 6-8k years.

One correction to Grok's statement. The HTM is no longer pegged at 1-2C above pre-industrial. That was an error or overestimate. Here, I'll let Grok correct himself after prompting by me: You’re right to call me out on the Holocene Thermal Maximum (HTM, ~9,000–5,000 years ago) temperature figure—I said 1–2°C warmer than pre-industrial, and that deserves a closer look. Modern reconstructions have refined this, and the global average isn’t quite that high. Let’s clarify what the data says, whether it’s global or regional (Northern Hemisphere/high latitudes), and square it up. HTM Temperature: Modern Reconstructions The HTM was a warm peak driven by peak Milankovitch forcing—summer insolation at 65°N hit ~525 W/m² (vs. ~475 W/m² today). Early estimates, like those I leaned on, suggested 1–2°C above pre-industrial globally, but newer work tightens that: Global Average: Marcott et al. (2013, Science), a key reconstruction, pegs the HTM at ~0.5–1°C above pre-industrial (1850–1900 baseline) for the global mean. They used 73 proxy records (marine sediments, pollen, ice cores) spanning 30°N–30°S and found a peak around 7,000 years ago—warm, but not 2°C. IPCC AR6 (2021): Cites a global HTM range of ~0.2–1°C above pre-industrial, with a best estimate ~0.5°C. It’s cautious—proxies are sparse, and averaging hides regional swings. Liu et al. (2014, PNAS): Another global take, using models and proxies, lands at ~0.4–0.8°C warmer globally, peaking 8,000–6,000 years ago. They note it’s not uniform—latitudes matter. So, globally, 1–2°C overshoots. My earlier figure was too loose—modern consensus leans toward 0.5–1°C for the world average. Northern Hemisphere and High Latitudes: A Different Story The HTM’s heat wasn’t evenly spread—Milankovitch juiced the Northern Hemisphere (NH), especially high latitudes, where ice and land amplify warming: 65°N Summer: Insolation was ~11% higher than today, melting Arctic ice and greening tundra. Greenland ice cores (GISP2, NEEM) show summer temps 2–4°C above pre-industrial at ~70°N—forests hit the Arctic coast (Kaufman et al., 2004, Quaternary Science Reviews). NH Mid-Latitudes: Pollen from Europe and North America (e.g., Renssen et al., 2012) suggests 1–2°C warmer summers than pre-industrial—think boreal forests stretching north. Polar Amplification: Models (Otto-Bliesner et al., 2017) and proxies (e.g., Alaskan lake sediments) peg NH high latitudes (60–90°N) at 2–3°C, even 4°C in spots, above pre-industrial. Winter cooling offset some, but annual means still hit ~1.5–2°C locally. The 1–2°C I cited fits better here—NH, especially 40–90°N, where land and ice feedbacks cranked the dial. My mistake was smearing that across the globe. Why the Global vs. Regional Gap? Southern Hemisphere: Less land, more ocean—SH lagged. Proxies (e.g., Tasmanian sediments, Shakun et al., 2012) show ~0–0.5°C warming, some spots even cooler due to ocean buffering and weaker insolation shifts. Proxy Bias: Most HTM data comes from NH land—Europe, North America, Greenland. Global averages dilute this with sparse SH records, dragging the mean down. Seasonal Tilt: HTM warmth was summer-heavy in the NH—winter insolation was lower, balancing annual averages closer to 0.5–1°C globally. Correcting My Figure The 1–2°C I tossed out earlier isn’t the global HTM average—modern reconstructions cap that at ~0.5–1°C above pre-industrial. It’s a better fit for the NH, particularly mid-to-high latitudes (40–90°N), where summer peaks hit 1–2°C, and annual means in the Arctic nudged 1.5–2°C. I should’ve flagged that distinction—global vs. regional—since the HTM’s a tale of two hemispheres. Eemian Tie-In Your Eemian comparison (~1–2°C globally) still stands out—its warmth topped the HTM’s global 0.5–1°C, melting more ice (6–9 meters above today vs. HTM’s ~2–3 meters). Today’s 1.3–1.4°C (2025 trend) splits the difference—past HTM globally, nearing Eemian’s lower end, but with CO2 speed, not Milankovitch patience. My Weigh-In You caught me—1–2°C was NH-centric, not global. The HTM’s ~0.5–1°C worldwide, with 1–2°C shining in NH high latitudes. Thanks for the nudge—keeps me honest. What’s your next thread—want to map this to ice or chase another era?

If you think that's impressive, you should see this discussion I had with Grok about natural climate variations, particularly the so-called Roman Warm Period. It's like talking with someone with infinite knowledge. Most would have called me a troll or "natural climate denier" or some pejorative. Grok understood me and knew my arguments better than I did! Just look at this partial exchange: Me: My beef is they don’t align with historical records or modern reconstructions. Grok: Me: Here are my biggest issues: the Roman warm period was once thought to be colder, belonging to the cold, Atlantic period. Historical records, including from Pliny the Elder, detail a number of frigid Roman winters with deep snows and frozen Tiber River. Grok: Me: Also, reindeer roamed much further to the south in Europe according to historical records. Wouldn’t that also suggest cooler temperatures in central and Eastern Europe? Grok: Me: It’s odd. I don’t think the Roman warm period was formally characterized as such until the 1990s. Modern reconstructions based on proxies don’t show that era to be particularly warm, nothing close to the Holocene thermal maximum. I suspect it was exaggerated to promote skepticism of AGW by suggesting more natural variability than actually occurred. Grok: Me: Most of the Roman vineyards in England weren’t even for wine! They were for some sort of medicinal product.

1931 is under 8 (4.1”), but this set is quite top heavy with the first two years averaging 22.8 inches. If the next two winters average less than that amount, the new running 10 year mean is guaranteed to be lower - even if both years are higher than the current 10 year running mean.

Records today at Zanesville (76), Wheeling (77) & DuBois (70).

Very impressive warmth. Unfortunately, having some problems embedding this Tweet / X-post. https://twitter.com/NWSPittsburgh/status/1899548043000623341

https://twitter.com/nwspittsburgh/status/1899548043000623341?s=46 NWS Pittsburgh @NWSPittsburgh A daily record high temperature was broken at Wheeling,WV: 74°F. The old record was 72°F, set in 1927. 3:48 PM · Mar 11, 2025 · 2,074 Views