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@Danitegue thank you for your message, but we do not provide historical data even 1 day. please follow up this link https://community.windy.com/topic/9/how-can-i-access-historical-data

@MintLin I already send you a private message

If the six conditions, we’ve covered in previous chapter, are met, the tropical cyclone appears. Let's now learn what phases there are to grow from the tropical disturbance of the atmosphere to a huge tropical cyclone.

It starts with a tropical disturbance

At the beginning of every tropical cyclone, there is a tropical disturbance or a wave that can be caused for example by thunderstorm going from a land above an ocean. In this phase, previously mentioned six conditions play a big role to start the engine of development.

What is a tropical depression

In the next phase, the wind rises and starts to circle a centre of the disturbance due to the Coriolis force. Now it’s called tropical depression and it is a measurable and observable object in the atmosphere with clouds slightly rotating around causing low precipitation.

Almost a Hurricane

When the wind speed reaches 39 mph (63 km/h), it is called a tropical storm. Tropical storm looks like a little hurricane, but it has no eye in its centre. It is all covered in clouds spinning around an invisible centre.

In this phase, the storm gets a name. It can stop growing here and the name will be already used for only tropical storm and not for a cyclone (like was a case with recent tropical storm Ivo that weakened to tropical depression). More on tropical storm naming in following chapters. Anyway, even tropical storms can make huge damage.

When Tropical storm becomes a Hurricane

Finally, tropical cyclone is a phase with wind speed above 74 mph (119 km/h). It has a fully developed eye in the centre and its structure is quite stable above an ocean.

There are different names for tropical cyclones based on location, they are called hurricanes in the Atlantic Ocean and north-eastern Pacific Ocean, typhoons in the north-western Pacific Ocean and simply cyclones in South Pacific and Indian Ocean.

Before we get to more details in the upcoming chapters, we’ll uncover the difference between tropical and extratropical cyclone in the next one. See you next chapter.

Štěpán Šubík

Prague based student of meteorology eager for science, who likes to learn, but also wants to live to the fullest every day. Follow me on Twitter.

Next chapters:

• What is the difference between tropical and extratropical cyclone
• What’s the difference between hurricane, typhoon, cyclone

Previous chapters:

• What is a cyclone
• What is a tropical cyclone

https://www.windy.com/-Satellite-satellite?satellite,27.118,-74.092,5,internal

As you've probably seen on news, two major oil facilities in Saudi Arabia were attacked with drones, the Abqaiq processing center and the Khurais oilfield. The facilities are run by Saudi Aramco, Saudi Arabia's state-owned oil giant.

The fires caused by the attack were so large, that the smoke could be seen from space. The strikes were claimed by Yemen’s Houthi rebel group.

Saudi Arabia fires seen from space

Satellite loop from September 15th, 2019 (8:00 a.m. to 2:30 p.m. UTC) reveals the smoke from the fires, which have since been controlled.

The Abqaiq facility seen below is perhaps the world’s most important oil installation. According to the EIA.gov, the plant has a capacity of >7 million b/d.

Most of the oil produced in the country [Saudi Arabia] is processed at Abqaiq before export or delivery to refineries.

According to Reuters, 5 million barrels a day of crude production had been impacted by the attacks - close to half of the kingdom's output or 5 percent of global oil supply. Later on Saturday, the Houthis said the attacks were carried out by 10 drones and promised to widen the range of their attacks on Saudi Arabia, which leads a military coalition battling them in neighbouring Yemen, Al Jazeera reports.

14 September 2019

Abqaiq oil processing center

https://www.windy.com/-Satellite-satellite?satellite,17.937,46.198,6,internal

How to use a route planner

We already introduced you to a route planner with many functions. The route planner provides information for cars, boats, and airplanes as well. You can plan your trip to be as long as you want.
We hope that this detailed description will be helpful for everyone!

In the left corner of the Elevation menu you can see units, which tells you how long the road is. By clicking on units, you can choose which units you need.

Below the units are Total ascent, Total descent, Max elevation, minimal elevation and on the bottom is Route detail, which shows you geographic coordinates and also allows you to download a scheduled trip in GPX and KML format or share your route.

• Total ascent = provides a total of all increases to elevation
• Total descent = is the sum of all height differences of those parts of the track descending.
• Maximal elevation = provides the highest elevation achieved
• Minimal elevation = provides the minimal elevation achieved

Car, hiking

• Temperature = How many degrees it will be during the trip
• Rain, Snow (mm) = How many mm of rain/snow there will be during the trip
• Wind (kt) = Force of constant wind
• Wind gusts = A gust, or wind gust, is a brief increase in the speed of the wind, usually less than 20 seconds.
• Wind direction = is reported by the direction from which it originates. For example, a northerly wind blows from north to south. In general, wind directions are measured in units from 0° to 360°, but can alternatively be expressed for -180° to 180°.)
• Winds are named for the direction from which they come, followed by the suffix -erly. For example, winds from the north are called “northerly winds” (north + -erly).

Airgram

• Symbols illustrate wind speed and direction
• Windy symbols at lower levels (e.g. at 1000 hPa) are shown relatively smaller than the same symbols at higher levels
• Lines labelled means pressure in hPa (hectoPascal)

The “standard” pressure on the surface (sea level) is 1013 hPa. As we go up, the pressure falls, so at 850 hPa we are at an elevation of 1500m (5.000 ft) at 500 hPa, 18.000 ft etc

The winds aloft are amsl. Actually are the winds on standard isobaric surfaces. For example the wind at 5000ft is actually the wind on a “surface” of the atmosphere where the pressure is 850 hPa.

Over mountains those “isobaric surfaces” may intersect* (cut) the orography (land surface). Thus, if you point on Everest and choose wind at different altitudes you'll find out that wind “stays the same” at all levels from Om (msl) up to 8.000m.

• Also here, all wind symbols show the same wind speed (25 kts)

VFR

Visual flight rules are a set of regulations under which a pilot operates an aircraft in weather conditions generally clear enough to allow the pilot to see where the aircraft is going
The weather must be better than basic VFR weather minima, i.e. in visual meteorological conditions (VMC)
The pilot must be able to operate the aircraft with visual reference to the ground, and by visually avoiding obstructions and other aircraft

• Rain, Snow (mm) = How much mm of rain/snow there will be during the trip
• Convective r. = thunderstorms during the trip
• Clouds, rain (mm) = How many mm of clouds/rain there will be during the trip
• Weather warnings
• Cloud tops (m) = At what maximum height clouds are
• Cloud base (m) = At what minimum height clouds are
• Surface visibility (km) = Surface visibility during the trip
• Dew point spread (°C) = Dew point spread during the trip

IFR

Instrument flight rules (IRS) is one of two sets of regulations governing all aspects of civil aviation aircraft operations; the other is visual flight rules.

When operation of an aircraft under VFR is not safe, because the visual cues outside the aircraft are obscured by weather, instrument flight rules must be used instead.
ATC monitors IFR flights on radar, or through aircraft position reports in areas where radar coverage is not available

• ISA difference = International Standard Atmosphere, is a model for the standardization of aircraft instruments
• Weather warnings
• Cloud tops = At what maximum height clouds are

BOAT

• Temperature = How many degrees it will be during the trip
• Rain, Snow (mm) = How many mm of rain/snow there will be during the trip
• Wind (kt) = Force of constant wind
• Wind gusts = A gust, or wind gust, is a brief increase in the speed of the wind, usually less than 20 seconds.
• Wind direction = is reported by the direction from which it originates. For example, a northerly wind blows from north to south. In general, wind directions are measured in units from 0° to 360°, but can alternatively be expressed for -180° to 180°.)
• Waves = How big the waves will be and their direction

How to choose your direction on the map

• Our automatic settings is LEFT TO RIGHT, but you can choose between 3 options
• On these pictures you can see 3 maps with the same road but with a different direction of wind

NORTH UP = We are going from point 1 to point 2, the wind is coming from the North, so we are going against the wind

BOTTOM TO TOP = We are going from point 1 to point 2, the wind is coming from the North, so we are going against the wind

LEFT TO RIGHT = We are going from point 1 to point 2, the wind is coming from the East, so we are going against the wind

Hope it helps!
Windy launches route planner

@aziz-mian hi, I am sorry we are not able to do this.

@picosta Could you please delete the app and install it again. It should be working now. Sorry for the problems

@rittels Hi, there is not a "right" method. We are using the first method - Interpolating the u and v vectors, results in the speed of the interpolated value being relatively lower.

@abhinavsingh009 @jummso @MikeGrif
thank you for your messages but we do not have this function.

A hardcore hurricane chaser, which is how Josh Morgerman describes himself on Twitter, has posted breathtaking video. And it's really hardcore...

Definitely takes you more breath than the Hurricane Hunters flights inside the eye of Dorian we’ve posted last week. Josh shot the Dorian footage in POV style himself at Abaco, that got the hardest hit by hurricane ever.

Watch full-length (a bit over half an hour long) video that brings you through whole experience from his point of view. Wow.

Related content

• Hurricane Dorian coverage including satellite imagery
• Probably the most amazing comment on Dorian you've ever read
• Watch Hurricane Hunters 10 hour mission into Hurricane Dorian in one minute

https://www.windy.com/-Satellite-satellite?satellite,internal