MegaMike

I don't remember exactly the process, but several researches wrote a paper about the thermodynamic/microphysical evolution of that mega band: https://journals.ametsoc.org/view/journals/mwre/143/10/mwr-d-14-00407.1.xml?rskey=cIrzIt&result=2

You mean for the Boxing Day blizzard? I attached an interpolation that I created using GHCND/PNS observations. I created 200 other interpolations/images. I'm sure I'm not the only one who did this... Right? Anywho, I created the plots to determine the most significant snowfall event since 1900 on a grid. If you're looking for snowfall maps since 2008, I'd recommend checking out the NSA product: https://www.nohrsc.noaa.gov/snowfall/ They create their plots using in-situ observations, SLR climatology, Stage IV precipitation analysis (from Radar), and other gridded analysis products: https://www.weather.gov/media/notification/tins/tin15-05bigrsc_snowfall_aaa.pdf

I added more events. When I'm running/waiting on simulations at work, I run atmospheric simulations that'd interest me. I also added radar mosaics superimposed with observations and Atlantic basin, tropical disturbance storm tracks (by year) from ~1850 to 2020. This is done solely out of personal interest. I definitely used audio from several members of this forum, if you'd like me to remove the audio from the videos, let me know :). Otherwise, if you'd like me to run an additional simulation, give me a date and I'll consider initializing one. These are strictly deterministic (WRFv4.2) simulations with additional post-processing (unified post-processor/a Python library) utilities. Despite using analysis data (not forecasted data for the IC/BC's!!!), some events performed surprisingly poor ('Nemo' and the 'Boston Debacle' snowstorm to name a few). All events were evaluated at the surface and aloft when applicable. If you'd like to view the script I use to plot or run the simulations, let me know. I automated most tasks (.py>>.ncl>>.csh).

Hey guys, I've been running WRFv4.2.2 simulations for funzies lately. I configured WRFv4.2.2 w/1 parent (12km) and one nested (4km) domain. My nested domain (4km) encompasses all of New York City. If you'd like to view graphics of some notorious weather events, click the links below ... Keep in mind, my focal point is New England so some of these events weren't that interesting for the New York City area. Winter Storms (testing extratropical namelist options) Jan, 2005 - https://www.youtube.com/watch?v=Pe_75ngrc8Y&li st=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd&index=5 Apr, 1997 - https://www.youtube.com/watch?v=uEmCRmaUPtY&list=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd&index=2 Jan, 1996 - https://www.youtube.com/watch?v=J4o1Nz9wdBw&t=136s Mar, 1993 - https://www.youtube.com/watch?v=kyZWFzDvS4k&list=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd&index=3 Feb, 1978 - https://www.youtube.com/watch?v=sm3ipMFoHoE&list=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd Tropical Events (testing tropical namelist options) Irene - https://www.youtube.com/watch?v=GNhYYvrQrPc&t=252s Bob - https://www.youtube.com/watch?v=FmbhsaFaC4k&list=PL7uw9vTkqQwrX5nzMSy4qFQbTqU9WCqha&index=1 Gloria - https://www.youtube.com/watch?v=60wBgKfBrHg&list=PL7uw9vTkqQwrX5nzMSy4qFQbTqU9WCqha&index=3 Freezing Rain Events (testing p-type algorithm): Dec, 2008 - https://www.youtube.com/watch?v=sNkfVaudVZ8&list=PL7uw9vTkqQwrfqeW1diEdDmR_wGGvgjZC

I ran additional simulations if anyone's curious. All of them are at the following paths. Winter Storms (testing extratropical namelist options) Jan, 2005 - https://www.youtube.com/watch?v=Pe_75ngrc8Y&li st=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd&index=5 Apr, 1997 - https://www.youtube.com/watch?v=uEmCRmaUPtY&list=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd&index=2 Jan, 1996 - https://www.youtube.com/watch?v=J4o1Nz9wdBw&t=136s Mar, 1993 - https://www.youtube.com/watch?v=kyZWFzDvS4k&list=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd&index=3 Feb, 1978 - https://www.youtube.com/watch?v=sm3ipMFoHoE&list=PL7uw9vTkqQwp1s4oh6TRd8qm6StglCkUd Tropical Events (testing tropical namelist options) Irene - https://www.youtube.com/watch?v=GNhYYvrQrPc&t=252s Bob - https://www.youtube.com/watch?v=FmbhsaFaC4k&list=PL7uw9vTkqQwrX5nzMSy4qFQbTqU9WCqha&index=1 Gloria - https://www.youtube.com/watch?v=60wBgKfBrHg&list=PL7uw9vTkqQwrX5nzMSy4qFQbTqU9WCqha&index=3 Freezing Rain Events (testing p-type algorithm): Dec, 2008 - https://www.youtube.com/watch?v=sNkfVaudVZ8&list=PL7uw9vTkqQwrfqeW1diEdDmR_wGGvgjZC Does anyone have any suggestions for my next 10 simulations? I'm looking for unique events. I'd like to try Hurricane Carol (1954 - test the reliability of ERA20c prior to 1985) and the Blizzard of 2013 next. Dec. 9, 2005 is really interesting too. Before any recommendation(s), I can run simulations with reasonable accuracy from 1978+ (so far) w/ERA5 and ERA20c reanalysis data.

So about those armored millipedes/centipedes... Is there a way to get rid of or prevent them from entering my property? I'm finding them everywhere around my apartment. They creep me out. Something keeps eating my plants too . I had to move them inside.

Glad you guys enjoyed it! There were a couple things that stood out to me: 1) The visibility observations for the RI station near Providence... The station dropped to 1 mile visibility at ~1pm on Feb 6th, then down to ~0.1 miles visibility for ~12 hours afterwards lol. 2) Wind gust >70mph in Boston. This was plotted twice... These observations were taken +-5 minutes from the simulation time stamp. 3) Several hours of mix/rain from Providence to Boston. I don't believe this occurred. For the ERA20C dataset, I can run simulations from 1900 to the current day. Some datasets go back <1900, but they likely won't perform well. I plan on doing this weekly for different events in and outside of the US out of curiosity. We'll see how the older simulations pan out, but the 78' simulation evaluated relatively well.

Offer me some feedback, please! I ran WRF (+ some additional utilities) from 1978-02-04 to 1978-02-09 (for sh!ts and giggles) and created plots for two different grids (parent domain - d01 and 1 nested domain - d02). I added plots of temperature, wind speed, wind gusts, visibility, precipitation type, etc... and superimposed observations when applicable. The still images were looped to create a video and I added audio to, "set the mood." Since I ran a simulation on a historical blizzard, I figured the board would find it interesting. Admittedly, my video editing skills are poor...

This methodology looks reasonable: https://carnotcycle.wordpress.com/2012/08/04/how-to-convert-relative-humidity-to-absolute-humidity/ You won't even need to convert your temperature (C) or relative humidity (%)... Just plug n' chug. To get kg/m3 from g/m3, just multiple g/m3 by 1kg/1000g == 1/1000.

I agree! It's a very good question. Now that it's been a few years, I'd rank it like this; FORTRAN, NCAR Command Language (NCL; which is no longer being updated), and Python. I develop script pretty often in NCL and Python for statistical and graphical reasons. FORTRAN's important because most, if not all, Numerical Weather Prediction programs are coded in FORTRAN. If anyone's curious, the code to run NWP (for the Weather Research and Forecast model specifically) looks like this: https://github.com/wrf-model/WRF/tree/master/phys - Select any .F file in that repository. For Python, the script will look like this: https://wrf-python.readthedocs.io/en/latest/plot.html (I mainly plot images with Python). NCL's pretty similar to this, but faster when working with .nc/.grb/etc... files though. In all honesty, if you learn one language, you obtain a basic understanding of them all.

No. Public websites keep snowfall calculations simple because 1) scripting Cobb's/Dube's algorithm is too computationally expensive 2) in the end, it doesn't matter which algorithm you utilize for forecasts or 3) they can't write the script. Besides what I wrote above regarding positive snow depth, 10:1 ratios is easier to compute: a) If they use a precipitation type algorithm (csnowsfc is boolean wrt snow-> 1==snow, 0==not snow): snowfall = csnowsfc*LWE*10. For snowfall, precipitation type algorithms perform well... Diagnosing mixed precipitation type is problematic though. Here's an article that provides results using "observed" data: https://journals.ametsoc.org/view/journals/apme/55/8/jamc-d-16-0044.1.xm. Go to Table 1. b) If they use microphysics scheme output (SR is continuous -> from 1==all frozen precipitation to 0==no frozen precipitation): SR*LWE*10. You occasionally see websites that state, "this product may include sleet..." They likely used this methodology since SR is a function of what a microphysics scheme diagnoses (mass/concentration of rain, ice, snow, etc...). If it diagnoses graupel, sleet, and hail, SR will include graupel, sleet, and hail as well. It depends on the microphysics scheme. Most modeling systems use Thompson's microphysics schemes which means rain, ice (sleet), snow, and graupel are included in SR. Websites should be more public about their methodologies. Some are vague as He!!. Another pet-peeve of mine, Pivotal provides Kuchera's algorithm for PAID members. Why? Nobody published a paper on its accuracy and I'm sure other SLR algorithms perform better.

That's a good question. The algorithm takes into account "gauge losses" due to melting, compaction, etc... caused by the land-air interface. If land isn't categorized by the model at a given grid point, 0/NaN values will be produced by the algorithm. That's why there are 0/NaN values along the coastline. The (very course) GFS categorizes those grid points/locations as "water." The website post-processes those maps from the GFS by, snowfall(t)=abs(snow_depth(t)-snow_depth(t-1))+snowfall(t-1) - t==time. snow_depth is calculated within the model though. For the coding/scripting weenies: https://github.com/wrf-model/WRF/blob/f311cd5e136631ebf3ebaa02b4b7be3816ed171f/phys/module_sf_noah_seaice.F [via WRF] - search for "SNOWH." I'm assuming the GFS uses the same subroutine. For the non coding/scripting weenies: https://www.wcc.nrcs.usda.gov/ftpref/wntsc/H&H/snow/AndersonSnow17.pdf - The "new snowfall" calculation is denoted by equations 2.a though 3... It's different than what most people are accustomed to on this site. It calculates snowfall by diagnosing snow density.

Thanks for the feedback, everyone! Today is NC + 2 for me. I'm still getting everything setup (furniture/internet), but I'm beginning to get a sense of the area. I live in a nice community surrounded by Massachusetts' equivalent of Route 1 on steroids (15/501). The only sketchy area I've seen so far is along 15/501 near Walmart, otherwise, not bad! Obviously, NC has a much different feel... Even the dirt looks different than in NE (more clay?).

I'm not too big into the NHL. I rank major league sports as; NFL>>>MLB~NHL>>NBA>MLS. The Pat's are my favorite team followed by the Red Sox, Bruins, then the Celtics. I mostly watch the B's and the C's during the playoffs with the occasional regular season game. Fun fact: the first Pat's game I remember is the AFC div. game vs. the Raiders. I have no memory of the Pat's having a losing record... Super impressive! Noted. I won't stick any of my appendages inside any dark, empty void I plan on moving back to MA after a year of work for the EPA. They want me to get the "EPA experience." After that, I can work remotely from anywhere I'd like. My time in NC will be ironic. I got my degree in atmospheric science because I love winter weather. My most fond memories involve snowstorms. To name one, during the blizzard of 05' (Jan 22-24), I remember seeing cars slowly becoming engulfed by snow w/near hurricane force wind. For nearly 12 hours, I remember pure whiteout conditions. When the event ended, I remember going outside and thinking to myself, "I feel like I'm on Hoth." In some places, the snow was taller than I. To this day, nothing compares... Oh! I was ~14 at the time so I was probably 4' 6'' or something like that... So nostalgic! I created snowfall maps for fun. You can view them here (only for the NE US) if you'd like: https://github.com/msw17002/Historical-Precipitation-Analysis/tree/main/Northeast_Snowfall Some new terminology here: Palmetto bugs and noseeums. The worse I run into are horseflies. They're super annoying! I was never bitten by one thankfully. So Magpie meant casual waving! I thought he meant something different lol. Thanks for clarifying that! I look forward to any winter or severe weather event! I'm severe weather deprived... I usually get nothing significant (severe) where I live now. The accents will be fun! I always like listening to different dialects. Oh, the anticipation!

This is great! My mother lived in SC for a few years and her fear of the local wildlife transcended onto me. I exaggerated a little bit for a laugh, but there's sincerity with what I wrote. From what I read online (probably not be reliable), spiders like the Brown Recluse and Black Widow are relatively common throughout NC. I presume this isn't entirely true or nothing to be worried about? I'm looking forward to experiencing the culture change! I imagine there's a pretty big difference b/n people from the NE and the SE in general. The only problem I foresee is that I don't barbecue and I don't watch college sports

Ah! I didn't see your second comment in this thread. That's what I figured though. Getting quality controlled snowfall data is extremely difficult even in the U.S. For my snowfall evaluations, I use the GHCND archive to retrieve historical snowfall observations. You can get snowfall, snow depth, liquid water equivalent, etc... from the ftp/https server for all available stations which may include China. I'd try giving it a shot if you haven't already done so. It might help you add more data points onto your map. https://www.ncdc.noaa.gov/data-access/land-based-station-data/land-based-datasets/global-historical-climatology-network-ghcn

Good to know! I'm mainly worried about spiders navigating their way into my apartment then biting my hand off (joking). That's my greatest fear. COVID might be on that list too since it'll be difficult to acclimate to an area that's partially shutdown. I'll be working with ORAU as private contactor for the EPA so basically graduate school all over again. I have a 6 month lease at the Reserve at Patterson Place in Durham. Their fitness center sold me on their complex. Would you suggest getting anything like a dehumidifier?

Hey guys, I'm moving to Durham, NC in several days and I wanted to ask, how should I prepare myself ? I lived in New England my entire life (MA->VT->CT->MA) and I'm mainly worried about insects/snakes. To be clear, I'm not worried about the weather...

If you couldn't get observations, how did you create your map? I'm assuming you approximated values based on your own judgment.?. Also, why China (out of curiosity)?

Pivotal doesn't do any weighting. Snowfall is readily available by the NBM itself. I wrote about it a while ago, but the NBM's (which is an ensemble) details can be viewed here: < https://www.meted.ucar.edu/winter/nbm32winter/ > You'll need to register first though. At this range, I'd recommend using it. It begins losing its advantages as the event begins to develop and a consensus becomes strong.

Different plotting scheme... Pivotal defined their bins from -60 to +120 w/increments of 1 (approximating here) so 180 different bins in total. StormVista defined their bins from -40 to +120 w/increments of 5 (32 total bins). Since Pivotal plots their images with more bins, it appears finer than StormVista's plots. Assuming that both brands are plotting the same model without interpolating, there should be no difference.

Is that near the Frog Bridge? I lived on Jackson St. several months ago. Meanwhile, I'm in West Boylston, MA for this event. I'll be moving to NC soon so I wanted to savor this [possibly] final snow event before I leave New England. ~3/4 inches of snow on the ground w/medium sized flakes. It has been snowing since roughly 10(ish)AM.

Good call (assuming it's a dam). I had to find the point manually, but it led me to the following metadata regarding that station: GHCND_IDENTIFIER, LAT, LON, ELEVATION_m, STATE, STATION_NAME USC00173588 45.4586 -69.8653 253.0 ME HARRIS STN If you're curious, that location observed 60 inches of snowfall for the denoted time range. The maximum for this event occurred at Pinkham Notch in New Hampshire. I might remove it from the map since it's pretty absurd or too wildly epic. The station observed 108 inches of snowfall which is 38 more than any other station lol. It was an "outlier," but based on the location, I kept it.

Good to hear! I ran the interpolation for all events listed here < https://www.ncdc.noaa.gov/snow-and-ice/rsi/societal-impacts > for the NE US. So there are 211 in total. I'm iterating from highest to smallest RSI (the sum of area/population impacted by climatological snowfall thresholds). At the moment, I have 19930312_19930315, 19960106_19960109, 19780204_19780208, and 19690222_19690228. I'm hoping I'll get some feedback for the interpolations (such as additional observations or ideas... The 4 Seasons!!!). I fully expect to redo some of these images to make them more accurate for my ultimate analysis. I'm surprised how detailed the GHCND archive is though. There's plenty of observations since 1900 for our area. Northwest Maine was the only exception so I had to be creative for that region. I could look at other historical events too. I just need the start and end dates (even dating back to 1900). Here are the final images I'll post until the other images process and I decide where to put them.

Great! Thanks, Will! dendrite, you can PM me.