MN Transplant

All records, of course.

Sets us up for tomorrow with the slightly higher 850s.

DCA joins the 98+ cohort

Screams dry downslope. Amazing.

Might be a fake 5-min 99 unless the NWS has confirmed it. The official ob was 98. IAD at least 98. DCA at least 96. 94.8 is the high at home.

The 5-minute ob reminder. There will never be a 98 degree 5-min ob (only the hourly obs at 52 or 53 past) because of the silly rounding that is done, but any 100 is legit.

It is all about finding lifeguards.

Since you and I have DCA/IAD identical, I really just need BWI to hit 100 and not RIC. Of course, we are both going to lose when IAD/DCA hit 100 tomorrow.

Our pool was hopping too, but they are open for two more weekends (and 4-8pm during the week).

DCA is running well ahead of yesterday while IAD is a touch ahead. The clouds hung around yesterday so the comparisons are a bit tough to make. My station is actually a degree behind.

March 1907 is amazing. There are 4 record highs that still stand including the hottest March temp (93).

98 at DCA. Believe that is the new high for the year.

Topped my high from yesterday. 94.5 and gross.

A lot of the entries are still in play. Stupid BWI pavement stopped working.

I was tracking IAD for a while earlier today but fell off the pace. Only 94.

93.4 is the high so far here.

These differences are just wild for Monday afternoon. The NAM seems way too humid at the low levels, but the GFS mixing depth is, uh, let's go with aggressive.

Yeah. This is a brutal image. The +2 period is basically ending in 2040, +3 in 2060, and +4 in 2080. Projected changes to mean annual snowfall (%) at Toronto, Ontario (a); Montréal, Québec (b); Halifax, Nova Scotia (c); Boston, Massachusetts (d); New York City, New York (e); and Washington, D.C. (f) for the three global warming levels. Relative changes with respect to the 1980–2009 mean are plotted for each CRCM5 simulation (symbols indicated in the legend). A kernel density estimation of the distribution of projected changes among the CRCM5-ClimEx simulations is shaded in the gray violin plots generated using the Seaborn package (Waskom, 2021). Within each violin plot, a smaller box plot is included indicating the median (white dot), 25th–75th percentile (dark gray box) and complete range of the CRCM5-ClimEx data (dark gray vertical lines). Values calculated from the pooled data for all 50 ClimEx members are indicated by the purple circles. Signal-to-noise ratio (S/N) calculated from the ClimEx data is indicated under each violin plot.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023JD038804 Plain Language Summary Snowstorms affect the highly populated regions of the northeastern United States and southeastern Canada every winter, disrupting ground and air travel and resulting in substantial socioeconomic impacts. Understanding how climate change may impact snowstorms is necessary for this region to prepare for the future. We explore how snowstorms in these regions may change in a future, warmer world using two sets of climate model simulations. We find that yearly total snowfall is likely to decrease over most of this region, with the largest declines to the south and smaller declines farther north. Despite these decreases, we find that the snowfall amounts that currently occur during the largest snowstorms are still likely to occur even in a much warmer future climate. Finally, we examine snowstorms that produce a large percentage of the annual snowfall during a single event. We find that the region where these big snowstorms relative to the yearly snowfall occur most often will shift northward in the future. In summary, while yearly snowfall is likely to decrease nearly everywhere in eastern North America, significant snowstorms will continue to occur, and some regions will see more of their yearly snowfall during a few large events.

https://journals.ametsoc.org/view/journals/clim/34/6/JCLI-D-20-0197.1.xml 5. Summary and discussion This study investigates effects of global warming on extreme snowstorms along the NEUS coast by conducting and comparing dynamical-downscaling WRF simulations driven with and without the mean climate change signal extracted from HiRAM historical and future simulations. The 93 observed snowstorms in 1980–2015 documented in G. Chen et al. (2019) were adopted as surrogates for studying the potential effects. Results show that the number of events with moderate and heavy daily snowfall (SWE greater than 10 mm day−1) at Boston, New York City, Philadelphia, and Washington, D.C. is decreased from 60, 54, 43, and 30 to 32, 29, 30, and 20, respectively (Fig. 7). In addition, although the rainfall increases in all four cities, total precipitation increases in the south (especially along the coast), where the rainfall is increased due to the warming-caused increase of water vapor content and upward vertical motion, but decreases in the north (especially along the coast), where the rainfall increase is overwhelmed by the snow decrease (Figs. 5–7). As a result, the precipitation distribution exhibits a southwestward shift. Another notable effect is that the frequency of mixed rain and snow and freezing precipitation events is increased in the north of NEUS (Figs. 8 and 9), attributed to the northward retreat of the 0°C zone and the expansion of the zone with temperature near 0°C.

Yeah, IAD 90 after a low of 54 today! So, IAD hit 90 in September and still had a negative daily departure. BWI 87, DCA 85.

The GFS is broken. The NAM's 95ish makes more sense.

It has never hit 100 at Dulles in September.

A truly remarkable W-E gradient in precipitation this meteorological summer.

Euro with more realistic mid-90s now for next week.