Tuesday October 27 2020 Forecast (7:30AM)

83 Comments

DAYS 1-5 (OCTOBER 27-31)

Discussion…

Keeping in mind our often-mentioned terrible performances by guidance, there are not a lot of changes in today’s forecast from what was written yesterday, so to summarize, after a very feeble performance by an approaching warm front yesterday, first not giving much rain, and second never making it through, we get into a northerly air flow today which turns easterly on Wednesday as high pressure passes north of the region. A minor disturbance may bring a touch of wet weather later tonight and early Wednesday. And then comes the much-hyped first snow threat of the season! Oh wait a moment, it’s not really much of a snow threat now is it? It’s a rain threat, which we need, and we may score some beneficial rainfall of up to an inch or so mainly from Thursday afternoon through much of Thursday night and into early Friday as low pressure passes south of the region. Some of the moisture from yet another Gulf of Mexico tropical system will be involved in this, but I do think a fair amount of that moisture will miss to the south. Yes, there will be cold enough air from the north getting involved with this system so we probably do see a change to snow in some areas mostly outside of I-95 (though cannot rule out flakes further southeast for a time) as things get ready to wind down on Friday. As for accumulation? No, not 2011. We may see some minor accumulation, possibly measurable, in higher elevations favoring north central MA and southwestern NH, as far as the WHW forecast area goes. By Friday evening, it’s gone, and it’s cold/dry. This sets up a very chilly but dry Halloween on Saturday, which also features the second full moon of the month (Hunter’s Moon).

Details…

TODAY: Lots of clouds, breaks of sun. Highs 52-59. Wind NW to N 5-15 MPH.

TONIGHT: Mostly cloudy. Scattered rain showers late evening and overnight. Lows 38-45. Wind N 5-15 MPH.

WEDNESDAY: Mostly cloudy. A chance of rain showers in the morning. Highs 51-58. Wind NE 5-15 MPH.

WEDNESDAY NIGHT: Mostly cloudy. Lows 41-48. Wind E up to 10 MPH.

THURSDAY: Cloudy. Rain likely, especially during the afternoon hours. Highs 46-53. Wind E 5-15 MPH, higher gusts.

THURSDAY NIGHT: Overcast. Periods of rain, may mix with snow southwestern NH and north central MA overnight. Lows 35-42. Wind NE 5-15 MPH.

FRIDAY: Overcast morning with rain except mix/snow likely especially northwest of I-95 with minor accumulation favoring higher elevations of north central MA and southern NH. Partial clearing during the afternoon. Highs 42-49. Wind N 5-15 MPH, higher gusts.

FRIDAY NIGHT: Clearing. Lows 25-32 except 33-40 urban centers. Wind N 5-15 MPH.

SATURDAY: Sunny. Highs 43-50. Wind N 5-15 MPH.

DAYS 6-10 (NOVEMBER 1-5)

Cold start then milder finish November 1 as another cold front approaches. Rain showers night of November 1 to early November 2 may end as snow showers as a shot of cold/wind arrives for the balance of November 2. Another quick-moving disturbance may bring a rain/snow shower early November 3 followed by more breezy and cold weather. Quick warm-up November 4 then cool-down November 5 but high pressure dominates with dry weather.

DAYS 11-15 (NOVEMBER 6-10)

Very divergent medium range guidance (no surprise), so for now going with mainly dry, maybe brief unsettled weather around November 7. A lot of up and down temperatures may occur during this period. Will fine-tune with time.

83 thoughts on “Tuesday October 27 2020 Forecast (7:30AM)”

  2. Thanks TK.

    Isn’t the second full moon of the month also known as a “Blue” Moon?

    Rather fitting for a full moon to coincide with Halloween night. Nice and “spooky cold” for the trick-or-treaters. Bundle up! 🙂

    1. I’m still debating what to do for halloween. We have candy but leaving it in a bucket means goodbye candy within a half an hour. If only the honor system could work.

      1. We are NOT doing it. Plain and simple. End of discussion.

        Boston is a Covid hot spot and I do not think it is right to do it
        at all.

        Our porch light will be off. No STINKEN candy here.

        1. JPD, good move on your part especially given your wife’s weak condition. It’s a wonder Mayor Walsh hasn’t already banned trick-or-treating by now like many other communities have.

      2. That might be the best thing to do given the current circumstances. Let the kids take as much as they want, and they move on to the next house. That way, you won’t have to be at the front door having to wear a mask, and having to supervise social distancing. In the end, it’s all about the “candy” for them anyway.

  3. Thanks TK !

    Zeta certainly has a nice anticyclone over it now, with the citrus fanning out nicely in all quadrants and the center itself is central to the deep overcast. It’s got a decent chance, I think, to intensify beyond current projections.

  4. Thanks TK
    Tom you were talking about Zeta intensifying. This tweet from Meteorologist Michael Ventrice
    ECMWF ensembles show a 10% chance that #Zeta intensifies into a Major Hurricane over the open Gulf of Mexico waters…

    1. All of the above seem reasonable except for 3 things:

      1. NOT taking into account the warm ground
      2. Surface temps will be mainly in the 30s above freezing.
      3. The Sun Angle is a factor, although it is comparable to about February 14th or so. Perhaps not too much of a factor.

      1. And I left out perhaps the most important factor!!
        The intensity does NOT appear to be all that great.
        Mostly light to occasionally moderate. Does not
        look like any heavy snow, at least not yet.

    1. Yes, chances are definitely looking good for some white ground across CT Friday AM away from the shore. Though chances are likely not as high as that map in reality as those are 10:1 ratios

  12. Interesting stat….the same will hold true for my area:

    Eric Fisher
    @ericfisher
    1h

    This will likely end up being one of the shortest gaps between accumulating snow on record in Worcester. May 9th to Oct 30th = 174 days.

    Between them it has been the warmest such period on record.

    Never boring?

  14. Nice blog by Judah Cohen this week. Unfortunately some early similarities to 2011 this Fall….

    https://www.aer.com/science-research/climate-weather/arctic-oscillation/

    Some excerpts:

    “In Figure iii I show the daily Eurasian SCE (snow cover extent) for October for the past fifteen years and on this date 2020 currently shares the bottom two spots with 2011. 2011 was also a La Niña fall and winter and I did find the Eurasian SCE tends to be lower in La Niña relative to El Niño falls. The snow advance index (SAI; Cohen and Jones 2011) is also currently below normal. Below normal SCE and SCE and SAI suggest a stronger winter PV and subsequently relatively mild temperatures across the mid-latitudes of the NH.”

    “There is the risk that the strong PV couples with the troposphere all the way to the surface (as happened for much of last winter) in the coming weeks, resulting in an overall mild pattern across the mid-latitudes of the NH. That the stratospheric PV is relatively strong in the fall is not that unusual in recent years but if the cold/negative stratospheric polar cap geopotential height anomalies (PCHs) couple with the troposphere, cold/negative PCHs in the troposphere is unusual in the fall. It last happened in 2015 and before that 2013 but especially 2011. Comparisons to 2011 seem to keep coming up and if it snows the end of the month here in Southern New England, that will be yet another eerie similarity to 2011. There was no significant weakening of the PV that winter and North America was very mild that winter, though Eurasia experienced widespread below normal temperatures. Though to be clear I am not expecting a repeat of the 2011/12 winter, at least not yet.”

  19. Ryan Hanrahan seems to have boarded the snow train for Friday in CT.
    We’re becoming more confident in a rare accumulating October snowfall Friday. Several inches possible in the hills and even some accumulation in lower elevations as cold air rushes in. More specifics as we get a bit closer and we can iron out the details.

  20. 9 years ago today, (10-27-2011) I recorded 1/2 inch of snow here, the first measurable snow of the season. Just 2 days (10-29-2011) later came the second and largest measurable snow of the season at 5.6 inches.

  21. Definitely seeing signs of a more suppressed outcome with this coming system. Less QPF to the north. I continue to think many people see snowflakes Thursday night into Friday morning, but anyone looking for a big event out of this will probably be disappointed.

    They’ll be a good cold shot to follow, then another one just a few days later. But November as a whole looks warm. Really warm. A true Indian summer likely awaits us.

      1. Well, it may be premature to go that way too if we get a warm spell in November. Still have a lot of things to figure out between now & winter forecast time.

    1. Only a matter of time before we see them pick up on the southward suppression which has been what most highs to the north have done to these systems for the last several months. But I want to see some consistency from here on.

  23. High Pressure positioned in Ontario transitioning its way to Quebec has been misplaced and mistimed in numerous models. The actual position of the high will cause southward suppression of low pressure, as dry air from the north simultaneously eats away at the northern edge of the precipitation shield.

    Sincerely,

    Snow Grinch

    1. HAHA!! Well, once again we’re on the same forecast track. For the record, my met. colleagues all are as well (at least the ones I have talked to so far today).

    2. No, just a realist. I love both TK’s style and your style. You both
      tell it like it is and NEVER wishcast as some mets do.

      That being said, I hope you are both wrong, even though I am certain you are correct.

      1. That RDPS forecast is HORRENDOUS. The GFS one is a little more reasonable given it’s a 10:1 ratio base, but still too high.

    1. There’s a little more with that disturbance. There is a threat of showers that I did not have in my forecast, but have updated since.

  27. Unfortunately NOLA looks to be right in the crosshairs of this one….

    Tyler Stanfield
    @TylerJStanfield
    34m

    Concerning evening imagery over the Gulf of Mexico as #Zeta begins to fire new convection and redevelop its inner core with very impressive upper-level outflow aiding it.

    Dicey 24 hours of strengthening ahead with decreasing SSTs near the coast likely its only impediment.

    https://twitter.com/TylerJStanfield/status/1321216833391857668?s=20

    And does a stronger than forecast hurricane upon landfall have any impact on our weather outcomes up here on Thursday/Friday? Probably not but will be interesting to see how it plays out….

  28. According to Eric:

    1. Flakes in the air for Boston
    2. Growing season ENDS this weekend
    3. Clocks “fall back” early Sunday 😀

    OK, OK. The 😀 is according to me. Eric actually hates falling back. 😉

    1. I love the switch back and forth between Daylight & Standard time. 🙂 People complain, but our length of daylight is a function of our latitude. 😉

  29. Incredible ice storm footage coming out of Oklahoma. One of the worst ice storms on record and it’s only October! Ice accretion over 1″ in many areas…

    Stephen Jones
    @Tornado_Steejo
    · 6h

    This is one of the worst ice storms I’ve ever witnessed! Trees are absolutely destroyed across parts of Oklahoma City with power out to over 50% of households. I can hear trees snapping for miles in either direction. #okwx #icestorm

    https://twitter.com/ericfisher/status/1321124570804400139?s=20

    And some additional tweets:

    https://twitter.com/Basehunters/status/1321160058277941251?s=20

    https://twitter.com/JacquiJerasTV/status/1321162516890820610?s=20

  30. You don’t see an ice storm warning issued in Oklahoma in October too often. I believe normal highs in October in Oklahoma are in the 70s.

    1. It’s definitely high mountainous. I hesitate to say somewhere in CA because they don’t usually get their mega snows with a southeast wind. It’s usually westerly. It could be somewhere in southwestern Canada. So I’m not 100% sure on this one.

        1. Takes Canada out of the running. I should have known that to start with based on the format.

          If it’s not Alaska, it’s West Coast somewhere, so I’ll just take a stab at northern CA.

                1. Love it! For a little while I was thinking somewhere around Anchorage. This is an area I didn’t forecast all that much for all the areas of the world I have done forecasting over the years.

                2. You’ve got mountain peaks in excess of 13,000′ only about 12 miles north of sea level. When those south winds get cranking off the Gulf of Alaska and slam into some very cold air in those higher peaks, I can imagine it just dumps snow, particularly higher up where the ratios are lower. To get snow amounts like what the NWS point and click showed, it would literally need to snow at 7″/hour for hours upon end.

                  I imagine when this happens in CA, OR, and WA state, the winds off the ocean have a westerly component as you noted, rather than the southerly component the south coastal mountains in AK need to see.

  32. Checking in to say hi, y’all.
    I have been out straight with hybrid teaching.
    It never stops. So much work!!!

    I got a Breaking News alert from The Weather Channel earlier today stating that Hurricane Zeta and Winter Storm Biily could merge.

    Would we call such a storm “Zilly?”

    I am so tired tonight, I am punchy.

    Good night, y’all!

    1. Naming winter storms is just plain ZILLY in my opinion. I’ll never agree with that. Ever. It’s probably in the top 3 all time most stupid media ideas related to weather. 😉

      If we have a massive icing event from warm and moist air flowing over the edge of an arctic high pressure area without any “storm” (no low pressure area), and yes this has happened many times, what are we naming? Tropical cyclones were named to identify the different entities that can exist. They are completely missing the point by naming winter weather events. They need to just stick to forecasting the weather and reporting on it. 🙂

  34. As I suspected not too long ago, a subtle shift eastward over the last several updates on the track for Zeta. Not a big shift, but a shift.

  35. Another example of our sucktastic guidance is it missing on this little low pressure area that is going to form over or just east of New England tonight / Wednesday. This probably has an impact on what happens with the next system. It will probably serve as yet another in a neverending string of examples of what I and other mets have been saying over and over about model guidance beyond a few days, and never more prominent than recent months. This even caused me to initially leave showers out of the forecast tonight / early Wednesday only to have to put them back in again. And there are showers out there. 😉

  38. Jeremy R. (Ch 7): “I don’t think I’m going to call it a snowstorm. Some might, but I’m just going to call it rain ending as some snow.”

    Tell it like it is, J.R. .. Love it 🙂

    I agree with his snow map which looks very similar to the 00z NAM Kuchera.

  39. Nice back-off to something more realistic by the GFS as well. See? As we get inside that 3-day window, the models’ performance vastly improves.

  41. snow is just about totally gone from the models now. What else is new. If it seems too good to be true, well the it is likely NOT.

Comments are closed.