First tropical storm of the season arrives 40 days early

GOES-East satellite captured this visible image of Tropical Storm Arlene on April 21 at 1145 UTC (7:45 a.m. EDT). Credits: NASA/NOAA GOES Project

The first tropical storm of the Atlantic Ocean hurricane season formed 40 days before the official kick off of the season. Tropical Storm Arlene formed in the North Central Atlantic Ocean and NOAA’s GOES-East satellite provided forecasters with a look at the storm, swirling far from land areas.

Arlene formed on April 20 as Tropical Depression 1 and strengthened into a tropical storm at 5 p.m. EST that day. On April 20 at 15:12 UTC (11:12 a.m. EDT) NASA-NOAA’s Suomi NPP satellite captured a visible image of Tropical Depression One as it was strengthening into a tropical storm. The image showed a large area of thunderstorms over the southwestern and northeastern quadrants of the storm.

NOAA’s GOES-East satellite captured a visible image of Tropical Storm Arlene on April 21 at 1145 UTC (7:45 a.m. EDT). Thunderstorms wrapped tightly around the center of circulation and a large band of storms circled west of center. Located to the west of Arlene were clouds associated with another frontal system.

The National Hurricane Center (NHC) said at 5 a.m. EST (0900 UTC), the center of Tropical Storm Arlene was located near 40.0 degrees north latitude and 48.0 degrees west longitude. That’s about 1,135 miles (1,825 km) west-northwest of the Azores.

Arlene was moving toward the west near 31 mph (50 kph) and this general motion is expected to continue today. Maximum sustained winds were near 50 mph (85 kph) with higher gusts. The estimated minimum central pressure was 993 millibars (29.33 inches). Arlene was beginning to lose its tropical characteristics as the cyclone interacts with a frontal zone and also moves over cooler water. The new official intensity forecast continues the trend of the previous advisory, which shows Arlene degenerating to a post-tropical cyclone by 12 hours, and dissipating by 24 hours when the system is expected to be absorbed into the larger baroclinic low.

The National Hurricane Center noted “Tropical storms in April are rare and Arlene is only the second one observed in this month during the satellite era. It should be noted, however, that this type of storm was practically impossible to detect prior to the weather satellite era.”

Little change in strength is expected, and Arlene is forecast to become absorbed by a large extra-tropical low pressure area and dissipate later today, April 21.

For updates on Arlene, visit NHC’s website:

[Note: the storm has already dissipated -Anthony]

65 thoughts on “First tropical storm of the season arrives 40 days early

  1. I am still in the Bahamas and it has been a much cooler winter and spring than any of the last 5 years. Storms are usually worse when it is cooling.

  2. That storm did not form in the Tropics and formed in temperatures much cooler than associated with tropical storms. It is an extra or subtropical storm. The NHC is full of it in the opinion of the truck driver because quite a few other storms that were better organized and that formed under similar conditions outside the tropical zone were unnamed by the NHC before this. They are moving the goal posts in order to try and up the number of named storms for the count and at the same time distorting the context of the historical record. NHC it seems is now in the same game as NOAA has been with temperature data. What’s next? Lowering the classification of past storms?

    • Agree 100% especially re stats. I would argue they have been doing this for a while, naming every little thunderstorm cluster they can, but this is disgraceful. Past NHC forecasters must be ashamed at this lack of common sense. Only reason it developed a warm core was because of the very cold air aloft from an arctic outbreak triggered strong thunderstorms around an already and initially cold core circulation.
      Makes the lowering trend in tropical storms even greater given this type of increase in storm detection.

      • I was under the impression that sea surface temperatures needed to be pretty high for tropical cyclones to form. Google tells me 80F. When I checked Arlene on last evening, air temps in the region looked to be 60-65F. Seems awfully cool for a “tropical” phenomenon. Not that I know anything about meteorology. Did have nice couterclockwise rotating precipitation though. (But so do Noreasters).

        • Same for winter storms that hit us here in northeast. Guess that means they, too, are tropical cyclones, at least according to the stuporgeniuses at NOAA.

    • My understanding is the storm formed in cooler than might be expected SST because the upper level temperatures were also low. This was a cool temperature event rather than a warm temperature event. It bears repeating. The heat engine could generally care less about absolute temperatures rather, runs on the differential.

    • RAH
      What a lot of nonsense.
      The term tropical storm is a measure of magnitude, not necessarily location.
      Try understanding why it occurred. Note that there was a cold snap in Europe displacing atmosphere at the same time. Exactly the same thing occured in January last year causing the hurricane in the Atlantic high latitudes.

      • It has to form in the tropics to count, as should be obvious. Otherwise it’s an extratropical, temperate or polar cyclonic storm:
        tropical storm
        A cyclonic storm originating in the tropics and having winds ranging from 39 to 73 miles per hour (34 to 63 knots; 63 to 117 kilometers per hour).
        American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company.
        tropical storm
        A tropical cyclone in which the surface wind speed is at least 34, but not more than 63 knots.
        Dictionary of Military and Associated Terms. US Department of Defense 2005.
        They often leave the tropics, but it’s where they form that matters.

      • The term ‘tropical storm’ is a ‘measure of magnitude’. (huh?)
        Let me guess…you were on that March for Science…weren’t you, go on…admit it!

      • Tropical systems, also called warm core systems, work on the vertical gradient. Extratiopical systems don’t, for they also use horizontal gradients. Subtropical systems are hybrids. I’d say this one was a subtropical storm. These used to be excluded from tropical systems many years ago. I want to say that in the 1980s, when satellite monitoring really became good enough, they started noticing these more often and began to include them with tropical systems, since they shared more features common to tropical systems compared to true extratropical ones.
        Anyway, as I recall it, a tropical storm needs little vertical wind sheer and a sea surface temperature of 77F/25C to get started. This seems to have been altered somewhat, since they say 80F/27C these day, but maybe that’s the hurricane threshold, which needs more energy and tend to be larger systems. So strictly speaking, a tropical storm may form outside of the tropics (23.44N to 23.44S), yet still count as a tropical storm.

  3. Joe B. notes it is a mid-Temperate storm. The ghost of Tom Karl, or his friends as they prepare to leave before they get tossed?

    • Who do you think is trying to make something of nothing? What is it that you think they are trying to make, and why do you think it is out of nothing? This seems to be simply a report about weather that is actually happening.

      • NOAA is trying to make something from nothing. Storms that live and die in the open ocean are of no interest to anyone other than seafarers. When was the last time you remember hearing about one? What they are “trying to make” is support for a narrative that is dying because it’s just not true.

      • Making something out of nothing is a much more interesting happening.
        I’ll start the popcorn.

      • Seaice1
        I’m a meteorologist, my thesis was on hurricane development. I know a few things about tropical cyclone development. This storm would not have even triggered interest in the past by the NHC. It was a mid latitude cold core low with a small thunderstorm cluster embedded circulation. So you ask “who would make something from nothing?”. People who are inexperienced or trying out new detection systems or trying to manipulate stats or trying to boost the AGW message. No doubt this is already doing the rounds as proof of AGW.

  4. OMG! Obviously a Climate Change associated condition. I’m surprised it hasn’t received more press. Arlene may be gone but won’t be forgotten.

  5. And crapped right the f*ck out, like anyone with a brain knew it would. Early season systems ALWAYS crap out.

  6. It helps them with their season # stats at the end of the season. Anything for The Cause.

  7. Those up-thread who suspect skulduggery in the naming of this storm might be interested in this NOAA publication, issued in 2001:
    A Tropical Storm is defined as:

    An organized system of strong thunderstorms with a well defined circulation and maximum sustained winds of 39 to 73 mph (34-63 knots).

    A ‘Tropical’ storm can form outside of the tropics at times, as Arlene seems to have done. The term describes the method of formation, not where it formed necessarily (evaporation of water from the warm ocean surface as opposed to horizontal temperature contrasts, such as occur in mid-latitude cyclonic storms).
    Arlene formed by the ‘Tropical’ method and her wind speeds reached 45 mph, so she qualifies as a named Tropical Storm according to that 2001 definition. No hoodwink to see here.

    • Sorry but this total BS. Storms like this form in the Mediterranean and even polar lows can develop warm core circulations. Are the NHC going to start naming these?
      This storm formed well into the mid latitude baroclinic zone. Not in the tropics. It had nothing to do with the tropics and should never have been named.

      • 2hotel9

        So, they changed the definition to fit their political agenda. Yep, no skullduggery there.

        The definition of sustained maximum winds >39 mph dates to at least 2001. See the above pdf link. That’s 16 years ago. Are you suggesting that NOAA changed the definition of what qualifies as a Tropical Storm back in 2001 so that it could claim, 16 years later, that Arlene was a Tropical Storm when really it wasn’t?

        • Bud, I grew up in the hurricane zone of the Gulf of Mexico, I remember Hurricane Camille. The changes in classification of tropical storms and hurricanes in 2000 were 100% agenda driven, not science. I have been following hurricane tracking since I was 10 years old and have witnessed the politicization of NOAA and other US governmental agencies involved with meteorology and climate sciences as well as the same in college/university systems. When “raising awareness” takes precedent over actual science then science suffers. This “tropical storm” is politically driven crap. Period. Full stop.

        • Oh, don’t I know it, brother, don’t I know it. I recall the days when NOAA pushed science instead of a political agenda. Perhaps in the coming year or so we can force them back to science.

    • DWR,
      You overlooked the “tropical” part of the “Tropical Storm” definition. You also missed this from your link:
      “Breeding Grounds
      “Hurricanes are products of a tropical ocean
      and a warm, moist atmosphere. Powered by
      heat from the sea, they are typically steered
      by high-level easterly winds while in the tropics,
      generally south of 25° north latitude and by
      high-level westerly winds north of 25° north
      latitude. When hurricanes become very strong,
      they can create their own steering winds.”
      This clearly indicates that tropical storms have to originate in the tropics, or at least the very lowest subtropics, ie lower than 25 degrees, before possibly moving out of them into the higher subtropics or temperate zones.

    • DWR54 Quote:
      A TROPICAL Storm is defined as:
      An organized system of strong thunderstorms with a well defined circulation and maximum sustained winds of 39 to 73 mph (34-63 knots)
      …I think the big clue here that you missed is word beginning with T in the first line of your definition…I capitalised it to help you.

  8. pbweather
    Tropical Storms arise in either the tropics or subtropics. Anything above 40 degrees latitude is classified as ‘temperate’, so Mediterranean storms wouldn’t qualify as Tropical Storms even if they had the same characteristics.
    Arlene began as a ‘Subtropical Depression’ at 31.9N on Wed Apr 19 and was upgraded to a ‘Tropical Storm’ once its sustained wind speeds exceeded 39 mph. The upgrade advisory was issued on Thu Apr 20, when its maximum sustained winds were measured at 45 mph. At that point it was at 37.7N.
    Arlene meets all the criteria required of a Tropical Storm, hence it’s naming. What, in your opinion, disqualifies it from being a named Tropical Storm?

    • The fact it damaged nothing and effected no one, and it was gone AS IT WAS being reported. Political horse sh*t, courtesy of NOAA.

      • Tropical Storms aren’t defined by the damage they cause. They’re defined as weather systems that start in tropical or subtropical oceans and reach sustained wind speeds of >39 mph. That’s been the definition since at least 2001. Arlene meets both of these criteria.

        • Yes, changing the definition, it serves their leftist agenda, not public awareness or safety. That is the point. This system was not a “tropical storm” and had absolutely zero chance of becoming a hurricane. The change in 2001 was meant solely to drive up the number of named storms in any given year which is purely a politically driven agenda. Not science. Not meteorology. And damned sure not any part of Hurricane Tracking.

    • DWR54
      l also have to call BS on this claim that’s it a Tropical Storm.
      l was forecasting low pressure over the Azores area of the Atlantic days ago due to the splitting of the jet over the North Atlantic.
      Just look at the picture of this storm at the top of this piece. Note how to the west of this storm the “cloud streets” are tracking north/south as a mass of colder air is flowing down from the north. While to the east of the storm the clouds are showing that warm air is coming up from the south of this storm. lts this mixing of air masses that is causing this storm. Not warm water. Next Thur/Fri will prove this is the case as a flow of colder air that started off over Eastern Canada will be pushed well to the south over the Atlantic. Which the jet stream forecast suggest will cause a quite powerful area of low pressure form south of the Azores. Which by the way the weather models don’t really seem to be picking up. But am going with the jet stream forecast on this one. Now lets see if NOAA also try and claim this as a Tropical Storm.

      • taxed

        l also have to call BS on this claim that’s it a Tropical Storm.

        The ‘claim’ that Arlene was a tropical storm arises from the verifiable fact that it met all the criteria for what NOAA considers to be a Tropical Storm. They didn’t just dream these criteria up last week; they’ve been in the published literature since 2001 at least.
        Re the weather system you refer to: if this arose over land and north of lat. 40N then it wouldn’t be called a Tropical Storm in any case. Tropical Storms have to arise in tropical or subtropical latitudes over water.

      • DWR54
        l can understand why there so keen to name this as a Tropical Storm. Because if this type of jet stream patterning lasts into the summer than it will be very likely putting a “brake” on hurricane formation. Because with the jet stream splitting over the Atlantic it will make the southern track of the jet stronger as colder air gets pushed south. A stronger jet over this part of the Atlantic will reduce the chance of hurricanes forming. So the storms linked to this jet streaming patterning are more likely to form as the colder air gets pushed over this part of the Atlantic ocean just like this one did. So they can link these early “Tropical storms” to the AGW agenda. Just when there maybe a risk of summer hurricanes decreasing.

    • DWR54
      Because in the past this storm would not have been named by the NHC. Other storms, much better organized and with higher winds forming in the approximately the same latitude have not been named in the past. Joe Bastardi gave two excellent examples of a couple of unnamed storms that were better developed and more powerful than this one and formed at approximately the same latitude. Thus the naming of this storm shows a lack of consistency and is a distortion of the tropical storm record. The goal posts have been moved. If that is not the case then show analogs to Arlene that have been named in the past as a Tropical Storm.
      BTW in todays Daily Update Joe pointed out that Arlene is not dead yet. It looped around to the south and is now headed east where it will die.

      • RAH

        Because in the past this storm would not have been named by the NHC.

        Not sure what you mean by “in the past” RAH? I linked above to a 2001 publication from NOAA/NHC in which they clearly state that a Tropical Storm is “An organized system of strong thunderstorms with a well defined circulation and maximum sustained winds of 39 to 73 mph (34-63 knots)”.
        How far back are you going and what is your source please?

      • Try the entire history of the National Hurricane Center but the examples Joe gave were from the last 30years

    • DWR54,
      The Med latitude extends from 30 deg N to 43 deg N. The Medicane formation region is usually south an east of sicily i.e. 30-37 deg N. So ykur reasoning is flawed.

  9. “Note: the storm has already dissipated -Anthony”
    But the game has just begun. The rare, early storm will be offered as “further proof of catastrophic climate change” and an uninformed public will buy it. The storm will serve a disinformation purpose.

  10. Now we see the word-smithing done by the gov’ weather services. This thing is just a regular cold-core low-pressure system.

    • Hell, they name “snow storms” now to ramp up the anxiety of the public. And they wonder why people laugh at them, at least when we are not ignoring them.

  11. “It should be noted, however, that this type of storm was practically impossible to detect prior to the weather satellite era.”
    Riiiight, so something which you ould only see on satellite images and which has dissipated in about 24 hours has got a name. By the end of the year we will be up to cyclone Zeberdee and people will be screaming about how it is “worse than we thought”.

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