Tonight, the brand new blockade ordered by President Trump after no deal with Iran and his prediction on gas prices come the midterms.

The countdown now on to tomorrow morning when the military says it will block all Iranian ports on the Strait of Hormuz after weeks of paralysis for oil tankers.

The move, threatening to escalate tensions and raise questions with both sides

far from a peace deal. Also tonight, global markets responding after the president says gas prices

could get even higher and how he's now defending that controversial threat he made to end Iranian

civilization. We're also tracking intense weather across the country. Take a look at this

funnel cloud there over Nebraska. Heavy rain flooding streets in West Texas. The new fire risk in

the northeast and in California, a spring snowstorm stopping these 18 wheelers in their tracks.

The California congressmen facing growing pressure tonight to resign,

denying accusations of sexual assault by a former staffer. Now, some lawmakers are floating,

expelling him from Congress. Dramatic video tonight from a deadly mass shooting. You see it here.

People running from the scene. We've got the latest on the investigation. New developments in the case of the mom missing in the Bahamas. A key deadline now to either charge or release her husband after she went overboard. The health alert tonight, autoimmune diseases spiking, but not enough doctors trained to treat them. And there's good news tonight about this couple's decades-long cherry blossom tradition,

inspiring others who've watched Love Bloom.

This is NBC Nightly News with Hallie Jackson.

Good evening. We begin tonight with what could be a major escalation overseas.

President Trump ordering the military to blockade Iranian ports starting tomorrow morning,

10 a.m. Eastern, in an apparent push to try and take control of the key strait of Hormuz.

We've talked about that straight so much during this war, with the flow of oil and gas in the region basically paralyzed.

And now the president's suggesting gas prices may not drop back down before the midterms, with the world watching to see if this new blockade threat could upend the fragile ceasefire in the region.

It's coming after those face-to-face peace talks between the U.S. and Iran seem to go nowhere

overnight. We have team coverage, starting with Kier Simmons at the site of those talks in Pakistan.

Vice President Vance departed Pakistan after sunrise, with no deal to show for negotiations that

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