Thread by @althecat

#MiddleEastRainEvent Update

Forecasts for the next phase in the ME Rain Event currently underway have changed considerably due in large part to the Storms in the Eastern Mediterranean not behaving as initially expected.

Here we see this morning's storm activity over Iraq.

Originally the storm over near the middle of this animation was forecast to move south over the North African coast and dissipate. How this storm evolved was always the key uncertainty in this event, and the revision in its path has significantly altered the impact of the event.

Specifically:
- Rainfall forecast over the Levant has increased
- Rainfall in the major (formerly dangerous) event over central Saudi has moderated.
- The event has slowed down - Forecast to end now on 22nd Jan rather than the 19th.

"Forecast rainfall forecast over the Levant has increased." 1/3

GFS forecasts accumulated rainfall:
1. Israel, Lebanon and Jordan 90 Hours
2. Syria 180 Hours
3. Iraq 120 Hours (has already received lots of rain)
4. ME Region 384 Hours.

"Rainfall in the major (formerly dangerous) event over central Saudi has moderated."

Animation Below:
GFS Forecast - accumulating rainfall from today, next 129 hours.

"The event has slowed down - Forecast to end now on 22nd Jan rather than the 19th."

To be precise, the first part of this event now ends on 22nd. But the wider pattern of higher than normal levels of water over the Middle East continues to the end of current forecasts 29/1

Iran also has a change in terms of impact from this event, but probably still faces significant flooding risk over the next five days.

Iran remains the most dramatically affected country in this event in terms of rain/snow.

This animation shows what appears to be the end of an unusually complex set of storms over the Eastern Mediterranean. A cold flow of dry air pushing south is partly responsible for rain along the the North Africa/Levant coastline from Tunisia to Syria.

Here is a corresponding rainfall forecast, also from the European @ECMWF model.

Longer term outlook:

The long term big picture indicates some change ahead. The incursion of Tropical Atlantic moisture into Europe appears to about to finally cease as cold dry air becomes dominant, and pushes south over the Sahara.

This is a zoomed in view of North Africa and ME which shows how this flow of cold dry air interrupts the flow of Atlantic/Amazon water (not altogether) but to some extent across the Sahara.

But what it also shows is significant continue water circulation over East Africa, in spite of this, including ongoing events in the ME which may produce rain.

The mechanism for this is a recycling process of water in the region noted in the last thread.

https://twitter.com/althecat/status/1480563786306121728?s=20

Tonight the next phase of this latest event is beginning with two parts. Rain along a very long front on the Mediterranean coast....

.... + the beginning of what I have described as the main event, a period of rain over central Saudi Arabia water streams combine coming from the West and South.

7 Day Rain forecasts (weather.com) for:
1. Jerusalem, Israel
2. Medina, Saudi Arabia
3. Basrah, Iraq
4. Makkah, Saudi Arabia