Marine Weather and Tide Forecast for Portland, ND

DISCUSSION
Issued at 249 AM CDT Sat Jun 21 2025

Synopsis

At midnight, an upper level ridge was located over Minnesota.
Just west of this ridge, across eastern North Dakota a shortwave trough was present, accompanied by widespread convection and strong gusty winds occurring ahead of the wave across North Dakota and western Minnesota. At the surface there was a boundary extending from southeast North Dakota into north central Iowa with a moist southeasterly flow advecting 70 degree dew points northwestward into eastern Minnesota and southeast North Dakota.

...Hot and Humid Conditions Today, especially south of a Fargo to Park Rapids line...

Short term models are in good agreement today, showing the upper level trough over North Dakota moving eastward across Minnesota through early Saturday morning. This will bring an end to the widespread convection. Meanwhile, the surface boundary is expected to remain nearly stationary across southern North Dakota and southwest Minnesota. South of this boundary today it will be another hot day. NBM guidance remains consistent with highs climbing into the mid 90s. Given the high dew points (above 70) spreading into the region on southeasterly winds, afternoon heat index values will easily reach or exceed 100 south of a Fargo to Park Rapids line. As a result a Heat Advisory has been issued for this area. Anyone with outdoor plans should take precautions to stay safe in the heat.

Marginal Severe Risk Today

In addition to the heat...there is a slight chance (15% or less) for a few isolated thunderstorms late today or early evening given the positioning of the surface boundary, increasing afternoon instability, moisture, and lift later in the day. However there is little evidence of any upper level support to enhance synoptic lift and therefore the storm potential remains low. CAMs are trending toward minimal development, but if a storm does form, it may be capable of producing wind gusts of 50-60 mph and hail. The Storm Prediction Center has placed the area under a Marginal Risk (level 1 of 5) to account for this low-end threat.

Slight Risk for Severe Sunday

Looking ahead to Sunday, the surface boundary over southeast North Dakota and southwest Minnesota will lift northward as a warm front ahead of a more significant upper-level trough approaching from the southwest. This upper wave will be located near the right exit region of an upper-level jet, supporting stronger synoptic lift. With better large scale ascent expected, the chances for thunderstorms increase late Sunday into Sunday night. Some of these storms may become severe, capable of producing wind gusts over 70 mph, hail larger than 2 inches, and possibly a few tornadoes.

Hot and Humid conditions will continue on Sunday

Heat will also remain a concern on Sunday, as the northward moving warm front allows hot and humid air to expand further into Minnesota. As a result, the Heat Advisory will likely be extended northward, particularly across far western Minnesota.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/
Issued at 1143 AM CDT Sat Jun 21 2025

VFR conditions will dominate for all sites through the start of the period. Around 14Z, low cloud ceilings are expected to move into the area, especially for KGFK, KDVL, and KTVF for the rest of the period; those three sites have a >40% chance via ensembles to drop flight conditions below VFR. Winds will primarily be from the north around 5-15 KTs with KBJI seeing lighter and more variable winds.

FGF WATCHES/WARNINGS/ADVISORIES
ND...Heat Advisory until 7 PM CDT Sunday for NDZ052-053.
MN...Heat Advisory from 1 PM to 7 PM CDT Sunday for MNZ006-009-016- 017-022>024-027-028.
Heat Advisory until 7 PM CDT Sunday for MNZ029>032-040.