9/30/2016 – Things Quieting Down

Good afternoon, and Happy Friday,

Will make this quick. We have one last area of rain to contend with… and band of showers that currently extends from the Carolinas into Ohio… this will rotate thru late tonight and early Saturday. It’s a slow mover, so this rain may linger into the mid-day hours, but after that, things will improve.

If you’re so inclined, you can see the national radar loop with the accompanying surface chart here.

For Hurricane Matthew, we’re not out of the woods, but the track in the latest models has shifted a bit to the east. With a blocking high to our north… if this storm were to track closer to the coast, it would be a disaster. You all know I’m all for interesting weather, but this is one I’d just assume miss. Latest data suggests we will indeed be spared, but it’s still a week away, so lots can happen.

Talk to you all later.

9/29/2016 – Heavy Rain – Where it Stands

First, the rain event has been largely a disappointment over north-central MD, where storm totals have been around or even less than an inch. To the south, we’ve seen reports of 5 to 8 inches near and south of DC and on the Eastern Shore. As mentioned in the forecast emails, we knew there was gonna be heavy rain, and I also kept repeating the exact placement of the heavy rain would be tough (if not impossible) to pinpoint. And honestly, I don’t know if any of the models got this right.

A couple links for the latest rainfall…

Map with plotted valuesfrom the NWS
Map with radar-estimated rainfall I ran here at the office

As far as “Are we done?”… man, I don’t know. The NAM says we have another round of soaking rain coming thru this afternoon and evening, while the GFS says that we’re basically done, keeping the core of the evening rainfall t our south. I’m guessing the heavy rain threat is past, but as mentioned previously, the local radar loop will be your best friend> Latest Local Radar Loop

The stuff we’re watching is actually the blossoming rain on the Eastern Shore, which is beginning to push northwest. My guess is we’re done for the day, or nearly so.

The main storm is not going anywhere, so while the rain intensity and frequency will diminish, the clouds and rain are here for the next 2 days, possibly three. I am afraid to say Friday and Saturday are going to be cloudy, showery days… and Sunday is looking iffy as well too.

Talk to u soon… watching soon-to-be- Hurricane Matthew for next week. More on that later.

E

9/28/2016 – Heavy Rain Threat

The heavy rain threat remains… but there’s wide disparity amongst the models where the core of the heaviest rainfall (5-10″ perhaps) will be. Case in point, this morning’s short-range “ensemble” models total rainfall thru Saturday afternoon (courtesy of the PSU Ewall) can be seen by clicking here or looking below. Anything in blue is less than an inch, green is 1 to 1.5″, and red is 2″+, while the greys are 4″ or more (white is +8 inches)…

sref-87hr-qpf

I don’t expect you all to dwell on this map or even totally understand it, just note each image denotes a separate model run, and the heavy rain is denoted by the dark reds, greys, and white… and while they all agree heavy rain is coming, they all have small but significant differences. The mean of all the models is the larger map in the top center. Anyway, it’s safe to say periods of heavy rain are likely starting this afternoon and lasting into Saturday morning. It won’t be non-stop, and there may even be peaks of sunshine… but the rain could at times be torrential. Again, the local radar will be your best friend.

Some subtle changes:

1) The models are slower with getting this out of here. For my family, this does not bode well for Saturday’s reunion. The worst of it should be gone, but the models show the threat of rain lingering into Saturday night due to our blocking high to the north.

2) A few folks pinged me about travel concerns for the weekend; for both the PA-bound crew and NY folks, the forecast is worse… wetter for sure. The PA folks may run into heavy rain, while the NY crowd will likely be spared the deluge that’s coming our way.

Heavy Rain Threat – Wed Update

First, for phones and other devices which don’t support Java or Flash, the local animated gif radar loop from Accu Wx will be a good source as any:

Our heavy rain event is unfolding. Blocking high to our north, while an upper-air low drops south from the Great Lakes and stalls to our west, enabling a butt load of moisture to work into the region aloft. The abundant moisture, a stationary high to our north, stationary low to our west/southwest, and the resultant squeeze play between the two occurring on top of us…..this is the setup for potentially heavy flooding rainfall over the next 3 days.

Models vary. The Canadian Hi-Res regional is forecasting a bodacious (always wanted to use that word in an email!) 6 to 10″ for MD and nrn VA. The NAM pulls the heaviest rain farther west into the mountains, with the I-95 corridor getting 2 to 3″. The GFS is a widespread 2 to 5″ event for everyone from the mountains to the bay. The rest of the agree with heavy rain… but they’re all over the place with where exactly it falls. Note, even if we “miss” the heavy rain (which I’m sure the folks in Ellicott City would prefer), we’re still looking at 1-2″ between now and Saturday morning, and that’s the low end.

Next week… a tropical low organizing east of the Antilles is forecasted to move west into the Caribbean over the weekend and strengthen, then turn north next week and head up toward the East Coast. The blocking high to our north is not expected to give any ground, and this sets the stage for a potentially interesting — if not dangerous — situation. It’s more than 7 days away, and as you can see with this week’s rain, getting the details in a forecast of any kind are difficult… and if we’re talking a week or more away, that’s “Dreamcast”. Yet even with the potential East Coast hurricane a week away, the long-range forecast models all agree this storm will threaten the Atlantic Coast. The Canadian and GFS bring it ashore in the Carolinas then up into MD/DE/PA toward the end of next week. The European is much slower, and has the storm south of Florida at the end of next week. Just something to keep an eye on. As always, your best bet is to keep an eye on the NHC website:

Talk to everyone soon.

Much-Needed Rain

Short-term Wx: Since the historic and catastrophic flooding in late July that did so much damage to Ellicott City, the rain has basically shut off… Especially along and west of I-95. Case in point: through yesterday, the last 30 days — at BWI — we have rec’d 0.73″ of rain, a deficit of over 3″, or 19% of normal. CLICK HERE to see the full-sized 30-day PNP map, or look below.

2016-09-27-030d-pnp

We need rain. And it looks like we may get that… as an upper low stalls to our west this week. As a result, we will have a persistent warm, humid, southerly fetch (low spinning counterclockwise to our west puts us on the east side of the low, with a southerly wind) for the next several days. Between the humid, almost tropical air… the stationary low to our west, and favorable upper-level “dynamics”… models are targeting parts of the Mid-Atlantic for 3 to 6 inches of rain (potentially more) from Wednesday into Thursday night. The latest run of the Canadian Hi-Res regional has model over 10” in central and nrn MD, though admittedly this seems a bit extreme. But you get the idea. At the very least, I’d think about putting Rain-X on your windshield… once you’ve scrapped the dust and bugs carcasses off.

The good news with this… once we get past Thursday, the storm gets so wound up that it starts to pull dry air in from the west… and that dry air works in to the south and east side of the storm, giving us some hope for a decent weekend.

On to the tropics: A currently unnamed storm is developing in the Atlantic (to follow it, check out: http://www.nhc.noaa.gov/), and the long-range models are having all sorts of fun with this for the middle to end of next week. I won’t get everybody worked up by showing you forecasts for next Wednesday from the 06z GFS or the 00z CMC , but that would be irresponsible of me. The Burning Bush (European Model) is much slower… keeping the storm well to our south all the way out to Day 10 (240 hrs), fwiw.

That’s a wrap…

Preliminary min temperature plot for Sunday morning (via Mesowest – a must-have website for the hard core weather hobbyists) shows we ended up rather uniformly in the middle 20s. Here’s a map of the min temps:
Mesowest prelimary min temperatures for Sunday morning, April 10, 2016.

Turns out, some folks got sleet and graupel yesterday (it was not hail, btw). Both form when there’s a warm layer aloft over top a cold layer that melts the snow, and then it refreezes before hitting the ground. If it totally melts (into a raindrop) and refreezes, you get sleet. If it partially melts and then refreezes, you get graupel.. which we got quite a bit of yesterday during the day. Here’s a picture of the graupel out this way yesterday:
Picture of graupel falling in Jacksonveille, MD, ~ Noon on Saturday, April 9, 2016.

Ultimately, we ended up with a period of heavy snow last night ~8:00-8:30, enough to coat the ground…
Picture of the snow falling in Jacksonville Saturday night, April 9, 2016.

Folks up in PA actually got a snow storm out of this, while we ended up in the novelty department.

Anyway, I think that should do it for the winter. Honestly, I sure hope so.

More Logical Weekend Forecast

Have a very busy day so will keep this short. Yesterday’s NAM forecast seemed a bit extreme, and the latest iterations of the various models reemphasize this. Is it still going to get cold this weekend? You bet. Are we likely to see some snow? Yup. Will we need to shovel? Nope. This all boils down to where the new coastal low will get going, and the models have shifted this north a bit to just south of Long Island. So rain and snow showers are likely on Saturday, but no historic snow… and that makes sense.

I will add, even sans snow, the GFS is wicked cold Sunday morning. It has teens (yeah, frickin’ teens!) over nrn MD, and low to mid 20s everywhere else. To see the GFS temperature forecast for Sunday morning, check out:

GFS temperature forecast for Sunday morning at 5 am, EDT.

Light blue is teens, medium blues is 20s, dark blue (offshore) in 30s… each line denotes an increment of 2°F.

This would be really bad news for many local folks, including garden centers, orchards, and vineyards. I hope the GFS is too cold… but it’s been pretty spot on all week.

Freeze Extent – Apr 5

Day 1 of our 2-day freeze event is more or less in the books. The preliminary morning low temperatures (via Mesowest) are in and included via the link below. Most folks in the central and eastern piedmont were ~ 27°F, +/- 2°. Farther north and west it was colder.

Preliminary morning low temperatures for April 5, 2016, from MesoWest.

For tonight (Tuesday night into Wednesday morning), models show a replay of these values across central and nrn MD/srn PA, but not as cold south of Baltimore… especially along and east of I-95. So if you live in the Piedmont, one more night of this fun.

As far as damage, anything that is really susceptible to a freeze (summer ornamentals, tropicals, tomato plants, etc) will be wiped out by temperatures that low. Otherwise, I think most of the major hitters are OK.

As far as the more advanced indigenous growth (fruit trees, grapes, strawberry plants), it all depends on how far along the plant is. Most blooming apple trees are good down to ~ 28°F, while peaches are good down to ~ 27°F. I don’t think our peach and apple trees were quite that far along… and consequently they were more freeze tolerant. In order to really impact tree fruit prior to flowering, you’re talking low to maybe middle 20s… and thankfully we didn’t see that. Strawberries and blueberries are fine… not far enough along to be impacted. Grapes should be able to tolerate readings down to ~ 25°F before seeing some impact, assuming they haven’t started to leaf out. For all these, you’d need to maintain the critical temperature for 30 minutes before seeing damage.

Will keep an eye on the weekend and keep you posted.

Tie It Down or Lose It

Quick note to reemphasize the winds we’ve got coming late Saturday night into Sunday morning. Latest NAM forecast for Sunday @ 5 am shows winds just above the surface sustained at ~25-30 knots, which adjusting that down to the surface gets us roughly 25-30 mph, with gusts potentially double that (50-60 mph).

NAM wind forecast (knots @ 10m, or ~ mph at the surface) for Sunday at 5 am.  Yellow is the can o' whoopass.

Expect downed trees and power outages, especially in the area in yellow (25-30 mph sustained) on the attached link/map.

Thankfully, winds will subside rather quickly, so any downed wires/trees should not be compounded by additional wind problems later in the day. In fact, NAM shows winds going virtually calm by sunset. Nevertheless, if you’ve got anything that is outside that could end up being donated to your downwind neighbors, act accordingly.

Battle Royale

We are in for a crazy 5-day stretch, with wild temperature swings and gusty winds.

We have the winds now, actually, though this is just an appetizer for what’s to come. Expect strong south winds to keep things mild today and Friday, and then a cold front slowly sweeps thru Saturday. We’ll go from the 70s on Friday to upper 20s and low 30s Saturday night into Sunday morning. Sunday looks very windy to boot, especially across central and northern MD. Wouldn’t be surprised to see a replay of last Monday’s power outages out in these parts.

We follow this with a strong warm front for Monday, just in time for Opening Day. It’ll be windy, but temperatures on Monday will bounce back into the 60s and low 70s. But the potential idyllic baseball day could get ruined still. A strong cold front will sweep thru during the afternoon, setting the stage for afternoon and evening thunderstorms, and some of these could be severe. Hopefully we’ll get the game in.

As if that wasn’t enough fun, models show an even colder air mass blasting into the region Tuesday morning. The latest GFS forecast for Tuesday morning is a bit unsettling, with temperatures well down into the 20s just about everywhere:

GFS surface tempertures Tuesday morning, April 5th.

Tuesday night, the high settles overhead… and our winds are forecast to go calm, setting the stage for yet another hard freeze Wednesday morning. Guess I’ll put the potted hibiscussessesses back into the basement. Damn.

So, we’re talking a freeze Sunday morning, and then a hard freeze Tuesday and Wednesday morning.

Welcome to April!