Newman

As has been discussed ad nauseam here, I don't believe there's anything to worry about regarding a colder and *potentially snowier* pattern setting up mid-December and beyond for the northeast. The SE ridge will be suppressed enough to allow the baroclinic boundary to slowly inch south and eastward towards the coast, the CPC map you shared is highlighting that (just compare weeks 3-4 to weeks 2-3). It won't happen in an instant, but the cold will try to bleed south into the northern Mid-Atlantic towards the second or third week of December which should offer chances of snow. The nuances in the flow are impossible to figure out at this point, hence *potentially snowy*. Fail mode is obviously if the -PNA overpowers any SE ridge suppression.

Yep I was wrong. The sheath was positive though which doesn't mean anything until we get into the flux rope which we've seen can instantly flip negative (or stay positive)

CME arrival appears to be running a bit behind the initial forecast of a 15-18UTC hit. Seeing indications of a 21-00UTC (4-7pm EST) hit instead, but I guess we'll see. And of course, we need a southward (negative) Bz for the storm to be geoeffective!

The red pillars were naked eye visible, couldn't believe it! Hoping tonight is even better, but we'll see.

Took this at 9:13 PM EST last night from Florida From my folk in Fleetwood around the same time:

Tallahassee FL tonight

Although the chances of a KU are inherently lower in a Niña with a less active subtropical jet, we've seen some big ones in Niña winters such as 1996 and, a few years ago, Feb 2021. My biggest concern for this winter is a relentless Pac Jet which is helping to push along this brief cold snap this week. We had a perfectly timed rossby wave break that dislodged a piece of the Polar Vortex southward into the Eastern US, amplified by a peaking +PNA ridge. But too much energy crashing into the west coast is keeping the flow too fast, so this deep trough is unable to deepen and turn negative as the ridge out west breaks down quickly. I feel like that will be a theme this winter... The Western ridge breaking down too soon. I hope I'm wrong though! I'm favoring a near-normal snowfall year for Philly which will feel well above average compared to recent years.

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Impacts in St. Johns/SE Canada from Melissa will largely depend on how far west it can get. The strongest winds will likely remain on the east side of the storm, so a miss east would keep any hurricane force gusts off the coast, though TS wind gusts would still be certain in areas

The dropsonde with the crazy winds came from the South/Southeast eyewall, the backside winds are going to be equally as intense

The center of the eye will actually go west of him

11am update still 185mph, 892mb

Yeah the jog north here right before landfall will get Josh head on in the eye

1935 Labor Day was the strongest ever Atlantic landfalling hurricane, by pressure, at 892mb. This will tie or surpass that.

There's the 10am update. WOW. 892mb and 185mph

Another thing to be reminded of... Much of Jamaica is well above sea level. For example, Mandeville (which could get raked by the eastern eyewall) has a population of 47,000 people or so and is at an elevation of 620 meters (2,000 feet). So I would absolutely expect higher gusts in those locations

NE Eyewall Sonde. 160(!) knot surface winds?

What looks like the coldest cloud tops we've seen yet wrapping around the southern CDO right now. Probably -95°C, maybe colder.

11:00 PM EDT Mon Oct 27Location: 16.6°N 78.5°WMoving: NNE at 2 mphMin pressure: 903 mbMax sustained: 175 mph

On Friday I listened to a briefing from the chief meteorologist for the Jamaican weather service and, at that time, the *center* of the NHC cone kept Melissa skirting around the western side of Jamaica. And in his briefing he stated "Right now, Jamaica should be protected as Melissa goes around the island". Like no sir, that's THE CENTER of the storm. Impacts are wayyyy outside the cone. I audibly gasped at his statement. I really really hope they are prepared for this.

Cat 3, 4, 5... Whatever the landfalling intensity is, I'm sure much of Jamaica does not have infrastructure built to withstand major hurricane winds. Really hoping a worst case scenario (i.e. right eye wall traverses through Kingston) doesn't happen.

12z Google DeepMind And 12z Google GenCast The *current* consensus is to slide it towards Western Jamaica before it turns north

I'd also want to emphasize that until Melissa starts to vertically stack and become better organized, there may continue to be disagreement in model guidance in the short-term because of their proposed placement of the final organized, stacked circulation.

Quite a shift east in the past day or so on the spaghetti hurricane guidance. The turn to the west is much shorter duration and Melissa gets pulled north and northeastward much quicker.

Here's the 12z EPS for reference. Right now, follow the ensembles. The clustering/highest probabilities keep it well off the coast. This is a complex setup and there will be lots of moving parts. The chance of a New England impact is still very low, but I do believe worth keeping an eye on. We've already seen this tropical season major shifts in guidance in the 7-10 day range vs what actually happened.