Date: 201810
Local time of day: 0601-1200
Location: MHTG.ARTCC, FO
Flight conditions: IMC
Weather elements / visibility: Thunderstorm; Rain
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb; Final Approach
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Distraction; Workload; Time Pressure
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation - Altitude Excursion From Assigned Altitude; Deviation - Altitude Overshoot; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Executed Go Around / Missed Approach; Flight Crew Took Evasive Action; Flight Crew Diverted; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Weather; Human Factors
Primary problem: Weather

Narrative: While descending into MNMG on the KOPAL 1A STAR around DANDO intersection and MANUA IF for the ILS DME Runway 10 Approach; after having been cleared for the Approach; the Tower advised our flight that the visibility on the field was now less than 1200 meters with heavy rain on and all around the field. The First Officer advised the Tower that we required 1200 meters and that we would have to terminate the approach. We were advised to climb to 3000 feet on runway heading and hold at MGA VOR. It was approximately at this time that the aircraft entered a violent updraft followed by a violent downdraft. There was yellow and green covering the weather radar screen but no microburst or wind shear alert given. The First Officer had his radar in the terrain mode for situational awareness. In my over 30 years of flight time with over 12000 hours alone in the 737 I have never experienced such an extreme up and down almost simultaneously. The autopilot was disengaged to manually fly the aircraft out of the weather and the First Officer assisted me in pulling the aircraft into climbing while caught in the downdraft. We had anticipated the ride being turbulent before we began our descent so the flight attendants had completed their service and taken their jump seats well before we encountered any severe weather.We had slowed the aircraft and configured to Flaps 1 when we were cleared for the Approach. We had not retracted the flaps when we encountered the weather and frankly I'm not certain exactly when I noticed the flaps were still at the 1 position or how fast we were going when I retracted them while working at positioning the aircraft onto the right heading and at the correct altitude. We both believe we were at approximately 280 knots. After recovering the aircraft into a climb we advised the controller that we needed a heading for ZZZZ and a higher altitude. We were cleared to FL190 and direct to on the STAR. We executed the ILS DME Approach at ZZZZ and landed without further incident. The aircraft was parked and the flap over speed was reported via ACARS to [Maintenance].


Second narrative: While on the approach into MNMG; we were given a visibility of 1300 meters from ATC for the ILS DME Runway 10; due to heavy rain. I was the pilot monitoring at the time of the event. Approximately 15 miles out on the approach; ATC informed us visibility had dropped to 1000 meters; which was below published minimums. We broke off the approach; the Captain disconnected the autopilot as ATC assigned us an altitude of 4000 feet. We were then given a clearance to hold at the MGA VOR as published. The Captain initiated a climb to 4000 feet; and I began searching for the approach chart that had the 'published' hold over MGA; as the ILS DME or LOC Runway 10 did not depict this hold; as is typical in Latin America. We then put MGA into the top of the FMC to go Direct. LNAV would not arm. This is when things got busy.I looked over and noticed that Captain was climbing through 4000 feet; overshooting almost 500 feet. I told him to watch his altitude and descend; and he responded he was doing his best; as he stated he must be in an updraft. I alerted ATC as to our altitude deviation; which was likely due to the heavy rain we were flying through; which did not appear convective on the radar. The Captain initiated a descent back to 4000 feet. He then asked me to build him the hold over MGA. I initially tried to select heading mode for him in the meantime; but the FMA showed us locked in VOR/LOC. I tried to select LNAV after inputting MGA VOR into the FMC. The command would not take; and the plane was locked in VOR/LOC. I assumed maybe it was still in Approach Mode somehow; so I tried deselecting; then reselecting the Flight Director for the Captain. This did not correct the situation; so we decided to just fly the airplane to MGA manually; and enter the hold. I then looked over; and noticed we were in a descent; passing through 3500 and airspeed accelerating. I was extremely alarmed; and I yelled for the Captain to pull up; to climb! He stated he must be in a downdraft; and that he WAS pulling up. We then went below 3000 feet; so I joined him on the controls; and I pulled to help him get the attitude to a positive attitude. At some points we were probably hitting 280 [knots] or more in the descent. We finally got a positive rate of climb; but the speed was still in the barber pole; and there was an incredible force on the control column to pull for a climb. We then struggled to keep the climb coming; and I told him to maintain at least 10 degrees of pitch up.I then began thinking of terrain; as we now were no longer descending; and I switched my map to Terrain Mode. I tried guiding him with the heading [bug] to the right to go back towards the MGA VOR (as we had already just passed it). I was never able to determine what the published hold was with all the confusion/excitement; and just had up the Terrain Mode while I tried to guide him to turn back to the MGA VOR. On the climb out; the Captain realized the flaps were still at Flaps 1; which we had both forgotten; since we never really officially started the ILS Approach. He called for Flaps UP; and I retracted the flaps. The Captain then decided that we should divert; instead to trying to salvage this holding pattern; to which I gladly agreed. We then climbed to FL190; and diverted without incident.Due to the fact that we certainly over sped the flaps in the 1 setting; we sent in an [electronic message] to [Maintenance] for inspection once on the ground. I later found out the Captain pushed the TOGA buttons to go around; and then a second time at some point during the climb. I do not know how this affected our use of the FMA; or the FMC; but I'm sure it was somehow related. Hard to determine when under this amount of stress.


Synopsis: B737 flight crew reported encountering severe weather on approach that resulted in a flap over speed and altitude deviation.